Design Study Report

ANTECY solar fuels development

Project runtime:

December 2014 – August 2015

Team members:

Alexander van der Made (Shell)

Robert Moene (Shell)

Tim Nisbet (Shell)

Saša Marinić (ANTECY)

Paul O’Connor (ANTECY)

Timo Roestenberg (ANTECY)

Subject:

Technical and economic evaluation of the ANTECY solar fuels process

Report author:

Timo Roestenberg (ANTECY)

Report date: 07-09-2015

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Table of contents 1 Executive summary ......................................................................................................................... 3

2 Project summary ............................................................................................................................. 5

3 Introduction ..................................................................................................................................... 7

3.1 Goal of the design study .......................................................................................................... 8

3.2 Approach ................................................................................................................................. 8

4 Background ...................................................................................................................................... 8

4.1 The technology ........................................................................................................................ 8

5 Project findings .............................................................................................................................. 11

5.1 Technical evaluation .............................................................................................................. 11

5.2 Economic evaluation ............................................................................................................. 12

6 Future perspective ........................................................................................................................ 13

Appendix I: detailed cost estimate of the 5 MW case .......................................................................... 17

6.1 Estimation of CAPEX of CO2 sequestration step .................................................................... 18

6.2 Estimation of CAPEX of hydrogen production by electrolysis ............................................... 22

6.3 Estimation of CAPEX of methanol synthesis ......................................................................... 24

6.4 Total main equipment cost ................................................................................................... 25

6.5 Real construction cost ........................................................................................................... 26

6.6 Discounting cost .................................................................................................................... 26

Appendix II: detailed cost estimate of the 500 MW case ..................................................................... 29

Appendix III: projected cost of PV and green hydrogen ....................................................................... 32

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1 Executive summary

The technical and economic feasibility of converting renewable energy produced by Solar (and or

Wind) into liquid fuels and/or chemicals were evaluated in a joint design study for a semi-commercial

and commercial plant. This study was performed by staff from Shell1 and ANTECY2.

The technology required comprises the following steps:

A. Production of electricity from solar energy via photovoltaics.

B. Production of hydrogen by water splitting (Electrolysis).

C. Capturing and concentrating CO2 from Air (and/or Flue gas).

D. Conversion of CO2 and hydrogen into methanol.

Steps A, B and D are based on state-of-the-art proven technology, while the technology for Step C is

under development by ANTECY and has been demonstrated (“Proof-of-Concept”) at a laboratory

scale.

The CO2 capturing and concentration process developed by ANTECY has certain distinct benefits over

competing technologies:

Reduced energy consumption by improved heat integration between the steps enabled by

the low desorption temperature of the adsorbent system, allowing the use of low value heat.

The use of an environmentally friendly non-degrading solid adsorbent system.

With regards to the technical feasibility of the overall process and the specific new technology to

capture and concentrate CO2, no technical barriers are foreseen to starting process development for

implementation at a semi-commercial (5 MW, approx. 2,6 kton methanol/year) and commercial

(500 MW, approx. 260 kton methanol/year) scale.

With regards to the economic feasibility at the present state of the technology and assuming a low

(but not zero) marginal electricity value of 0.02 € /kWh a 500 MW commercial plant would not yet be

profitable.

But the expectation is that the following developments can lead to improved economics within a 10

to 25 year timeframe, being:

1. An expected strong reduction of the electrolyzer CAPEX costs.

2. An increase of the overall energy efficiency of the process (Steps A to D) from ± 50% to 60%.

The implementation a CO2 tax, of ± 40 €/ton CO2 or more can also have a significant positive effect

on the overall economics.

The above is not yet taking into account further anticipated improvements in electrolyzer energy

efficiency and the closer integration of electrolysis with solar energy captured either by super-

photovoltaics (increasing solar energy capturing efficiency from ±20% to 40%) or other improved

forms of solar energy concentration.

1 Shell Global Solutions International B.V., Amsterdam

2 Antecy BV, Hoevelaken.

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The interplay between scale-up and cost reductions in electrolysis and CO2 capturing is expected to

lead to a point where CO2 capturing and utilization with renewable energy (electrons) becomes

interesting.

Therefore there is a sufficient incentive to further develop and scale-up this technology and

demonstrate the critical parts on a pilot and demo scale. The recommendation is for a next step to

set up a project team to address this. ANTECY will lead this effort while the proposal is that Shell will

continue to participate and support the project in the project definition phase, by jointly establishing

the risk factors, and the scale and sequence of demonstration and de-risking.

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2 Project summary

This report outlines the findings of the six month design study that was executed in a joint effort

between ANTECY B.V. and staff from Shell Global Solutions International B.V. The goal of the study

was to evaluate the technical and economic feasibility of the Solar Fuels process under development

by ANTECY, and to pinpoint those areas that merit the most improvement efforts. The Solar Fuels

process under development by ANTECY sequestrates CO2 from ambient air, splits water in hydrogen

and oxygen by means of electrolysis, and reacts the hydrogen and CO2 in a thermocatalytic reactor to

methanol, using renewable energy. Renewable energy is thus stored in a chemical that can be

integrated in the existing fuel and carbon-chemicals infrastructure.

The approach for the design study was to consider two cases. Firstly, a design and economic

evaluation was done for a process that has a power input of 5 MW. This case was evaluated based on

technical feasibility and scalability. The economic evaluation was done by obtaining estimates for the

main equipment, which was then multiplied by realistic multiplication factors that are common

practice at Shell, to arrive at a total capital investment cost. Based on the 5 MW case (approx.

2,6 kton methanol/year), a translation step was made to a 500 MW (approx. 260 kton

methanol/year) case using customary scale up rules. The results of the translation were cross

checked to figures of known installations of comparable processes at similar scale.

The main conclusions of the study are as follows.

With respect to the technical feasibility: key innovations made by ANTECY in this process are the CO2

sequestration and the energy integration between steps of the process. Each of the process steps

were individually evaluated on technical feasibility, as well as their integratability.

Renewable energy generation at both small and large scale has been demonstrated. Both

efficiencies and economics are improving, and expected to keep doing so over the years to

come. The footprint of the Solar Fuels process itself has been calculated to be 10-20 % of the

associated required large scale solar power generation system.

The CO2 sequestration process developed by ANTECY is deemed technically feasible, with no

technical barriers to development identified. It is also the process step that will require the

most effort to bring from current development state to industrial application. It is also the

only step that in the process that is entirely new, all other process steps have been proven on

industrial scale and are readily available.

Water electrolysis is a mature technology that can be bought off the shelf. Still progress is

needed (and expected) in terms of energy efficiency and, in particular, CAPEX, in order to

improve the economics of Solar Fuels production.

Methanol synthesis from CO2 and H2 is also a mature technology possible with commercially

available catalysts and reactor designs. Selectivity and activity of the process have been

shown to be competitive with alternative routes.

The mass and energy flows of the different process steps have been calculated to make

integration into a viable process possible. Heat generated by the hydrogen production and

methanol synthesis can supply the heat required for the CO2 sequestration step.

Methanol is deemed to be a good target product for a Solar Fuels process, because it forms a

dense and easily integratable energy carrier in the current energy infrastructure and because

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it forms a platform chemical for the production of carbon-chemicals such as olefins and

aromatics.

In conclusion it was found that no technical barriers are foreseen by the team to starting process

development for the implementation of the technology on a 5 MW to 500 MW scale.

With respect to the economic feasibility: a cost estimation was performed for the Solar Fuels process

at 5 MW and 500 MW scale. In the estimation current costs for equipment were used and a flat rate

of 0.02 €/kWh3 was used for energy required, with an assumed availability of 24h per day. For the

process to be economically profitable the cost of hydrogen production by electrolysis needs to be

reduced. This is illustrated in the charts in Figure 1 and Figure 2 where it can be seen that, especially

in the large scale case, the electrolyser cost is a substantial part of the total cost. It is projected that

the required improvements in electrolysis economics may occur in the 2025 and beyond timeframe.

It is the conclusion of the team that the results of the design study justify piloting the technology at

this time. The pilot should focus on the novel aspects of the CO2 capture technology to test the

validity of the assumptions made in this design study. The recommendation is for a next step to set

up a project team to address this. ANTECY will lead this effort while the proposal is that Shell will

continue to participate and support the project in the project definition phase, by jointly establishing

the risk factors, and the scale and sequence of demonstration and de-risking.

Figure 1, Cost breakdown of the 5 MW case (blue: hydrogen production, red shades: methanol synthesis, green shades: CO2 capture), total CAPEX 14.2 mln€.

3 Current (2014) bulk, grid energy price in the US is approx. 0.04 USD/kWh.

29%

11%

4%

25%

2%

4%

12%

6% 7%

CAPEX 5 MW

Electrolyzer

H2 compressor

CO2 compressor

Reactor

Vacuum pump

Desorber tank

Blower

Adsorber

Sorbent

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Figure 2, Cost breakdown of the 500 MW case (blue: hydrogen production, red shades: methanol synthesis, green shades: CO2 capture), total CAPEX 748 mln€.

3 Introduction

This report outlines the findings of the six month design study that was executed in a joint effort

between ANTECY B.V. and staff from Shell Global Solutions International B.V. The goal of the study

was to evaluate the technical and economic feasibility of the Solar Fuels process under development

by ANTECY, and to pinpoint those areas that merit the most improvement efforts.

The Solar Fuels process under development by ANTECY sequestrates CO2 from ambient air, splits

water in hydrogen and oxygen by means of electrolysis, and reacts the hydrogen and CO2 in a

thermocatalytic reactor to methanol, using renewable energy. Renewable energy is thus stored in a

chemical that can be integrated in the existing fuel and energy infrastructure, as well as form the

basis for a range of green chemicals.

For the study, two main design cases have been considered for the solar fuels process. Firstly, a

design and economic evaluation was done for a process that has a power input of 5 MW (approx.

2,6 kton methanol/year4). This case was evaluated based on technical feasibility and scalability. The

economic evaluation was done by obtaining estimates for the main equipment, which was then

multiplied by realistic scaling factors that are common practice at Shell, to arrive at a total capital

investment cost.

Based on the 5 MW case, a translation step was made to a 500 MW case (approx.

260 kton methanol/year) using customary scale up rules. The results of the translation were cross

checked with figures of known installations of comparable processes at similar scale.

Finally, a technical and economic evaluation was done for the CO2 capture part of the process,

applied to flue gasses, specifically, compared to state of the art amine processes.

4 The energy equivalent of one ton of methanol is approx. 3.2 barrels crude oil.

48%

5%

2%

10% 1%

7%

5%

10%

12%

CAPEX 500 MW

Electrolyzer

H2 compressor

CO2 compressor

Reactor

Vacuum pump

Desorber tank

Blower

Adsorber

Sorbent

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3.1 Goal of the design study The goal of the design study is to evaluate the technical and economic feasibility of the ANTECY solar

fuels concept, today and in the future. For the economic feasibility an accuracy target of ±50% was

desired.

3.2 Approach To achieve this evaluation, the technical design was discussed and, where needed, modified. For

each of the main components, cost estimates were obtained. These were used for a CAPEX estimate.

This was done for a 5 MW size installation. Subsequently, scale up rules of that are common

engineering practice were applied to estimate the CAPEX of a 500 MW size installation. The results of

the translation were cross checked with figures of known installations of comparable processes at

similar scale.

The reason a 500 MW size for the calculation was chosen is that this was deemed to be a realistic size

to be compatible with large scale sustainable energy generation. Typical large scale sustainable

energy generation systems, such as large scale solar PV and large scale concentrated solar power

plants, that have been constructed and are planned for the coming years, are in the 500 MW scale

range. However, the results obtained for the 500 MW case can be extrapolated to larger sizes using

the same scale up rules outlined in this report.

4 Background

4.1 The technology The ANTECY solar fuels technology consists, in its simplest form, of three main steps. Firstly, CO2 is

sequestrated from either air or a different CO2 containing gas stream (such as flue gas). At the same

time, water is split electrochemically to form hydrogen and oxygen gas. The hydrogen gas is reacted

with the CO2 in a thermocatalytic reactor to form methanol5. In this way, sustainably generated

electricity is stored in the form of a liquid fuel. This is schematically shown in Figure 3.

Additionally, the oxygen produced could be monetized to increase the profitability of the process,

but this was not included in the scope of this design study.

Of the technology, the latter two steps can be considered “state of the art” and technically proven;

both water electrolysis and CO2 hydrogenation to methanol are applied on varying scales. The CO2

sequestration step is the most novel, and at the same time the step that ANTECY has spent most of

its efforts on developing.

The CO2 sequestration process developed by ANTECY, named CAIR, comprises a sorbent (a hydrated

form of potassium carbonate on a support) and a specific process developed to efficiently use the

sorbent. In Figure 4 the process for producing pure CO2 from a CO2 containing gas is schematically

shown. The process is a cyclic process, where the CO2 containing gas is contacted with the sorbent

under ambient conditions. The sorbent is then heated under reduced pressure in the presence of a

flow of water vapour. The water vapour serves as a scavenging gas to retrieve the released CO2. The

CO2 can be easily separated from the water vapour by condensation.

5 Methanol is just one example of a potential product; alternative products include Fischer-Tropsch liquids.

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Figure 3, Schematic representation of the solar fuels process.

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Figure 4, Schematic illustrating the CAIR process principle.

There are variations possible to the CAIR principle as illustrated. For example, it may be

advantageous to have the adsorption and desorption taking place in different reactors. In this way,

the adsorption reactor can be optimized for contacting the CO2 containing gas with the sorbent,

under ambient conditions, while the desorption reactor is designed for the desorption process, at

higher temperature and reduced pressure. In this way one desorber can be used to regenerate the

sorbent of multiple adsorption reactors. This can, in the case of for example CO2 adsorption from air,

reduce capital cost. An additional advantage is that the height/width ratio of the adsorption reactor

can be made very low (in the order of 1/40), reducing pressure drop and thus reducing operational

cost. This example is illustrated in Figure 5. Further details on the dimensions are available in:

Appendix I: detailed cost estimate of the 5 MW case.

Figure 5, Schematic of the CAIR process using two reactors.

The sequestration of CO2 is done by means of a solid salt that is deposited on a carrier. Specifically, a

hydrated form of potassium carbonate is used. The chemical reaction that takes place is:

𝐶𝑂2(𝑔) + 𝐾2𝐶𝑂3 ∙ 1.5𝐻2𝑂(𝑠) ↔ 2𝐾𝐻𝐶𝑂3(𝑠) + 0.5𝐻2𝑂(𝑔)

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In this reaction the hydrated form of potassium is potassium carbonate sesquihydrate. However,

there are many other hydrated forms of potassium carbonate possible, depending on the conditions

of the reaction.

The advantage of the reaction with a hydrated form of potassium carbonate, as opposed to an

anhydrous form, is twofold. Firstly, the reaction enthalpy is lower, meaning that the amount of

energy that needs to be spent to reverse the reaction (desorb CO2 from the sorbent) is lower, thus

also reducing the reaction reversal temperature6. Secondly, since water is a product of the

adsorption reaction, and a reactant for desorption (as opposed to the opposite when using the

anhydrous reaction mechanism), the equilibrium of the desorption of CO2 can be shifted by

desorbing in a moist environment.

The footprint of the process, as described above, is a factor of 10-20 % of the footprint of the large

scale solar power generation plant of the same capacity7. Since it is likely that not the complete

capacity of the solar power generation will be used for solar fuels production, this will make the

required footprint of the solar fuels system relatively even smaller.

5 Project findings

5.1 Technical evaluation The solar fuels production process consists of four main components: energy generation, CO2

capture, hydrogen generation and methanol synthesis. The entire process has been simulated in a

flow sheet, calculating mass and energy flows of all mayor components. The technical evaluation of

the four main process steps will be discussed separately.

Energy generation

The energy required for the process can be generated by various means, all of which are already

applied on industrial as well as some on residential scale. Photovoltaics have been improved greatly

over the last decades, both in efficiency as well in production costs. The same can be said for wind

turbines. Large scale solar thermal plants are also already applied, although only a handful exist

around the world currently. So, more progress in large scale CSP (Concentrated Solar Power) can be

expected in the future. Since there is a multitude of options for energy generation that can be

combined with the Solar Fuels concept, each with their own merits, drawbacks and costs, a flat rate

of 0.02€/kWh was assumed for the cost of electricity in the calculations of this design study.8

Appendix III: projected cost of PV and green hydrogen, presents the base case and more aggressive

scenarios we used for costs of solar PV electricity up to 2050.

The various options with their varying levels of maturity do not inhibit the feasibility of the

application of Solar Fuels. In fact, the increasing market penetration of sustainable energy sources

and associated cost reductions only adds to the viability of Solar Fuels.

6 For the reaction shown, the reaction enthalpy is -41 kJ/mol, while the reaction enthalpy of the corresponding

anhydrous potassium carbonate reaction is -141 kJ/mol. 7 The land use of solar PV power generation is about 10,000 m

2/MW (1 GW plant, 20% solar cell efficiency),

while the CO2 capture, which constitutes the bulk of the land use of the Solar Fuels process, is approx. 1100 m

2/MW.

8 NB: the flat rate of 0.02 €/kWh includes the cost of storage of intermittent solar PV power, if PV is used.

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Energy intermittency

One key aspect of many sustainable energy generation options is their intermittent nature. This

intermittency manifests itself from rapid (order of minutes-hours) fluctuations, to slow (weeks-

months) fluctuations. While the Solar Fuels is ideally suited to be used as a long term energy storage

(and can thus be employed to solve problems with slow fluctuations), short fluctuations effect the

economics of the process. In order to meet the short term fluctuation, the Solar Fuels technology can

be combined with a short term energy storage solution. Since there are many options for short term

energy storage, such as batteries, compressed air energy storage, capacitors, molten salts. The ideal

solution is dependent on the application location, the choice for short term energy storage type is

left out of the scope of this design study, and assumed to be included in the future cost of electricity.

CO2 capture

The CO2 sequestration step is the most novel, and at the same time the step that ANTECY has spent

most of its efforts on developing. For this reason, the CO2 sequestration technology has been

analysed in most detail within this design study. During the different meetings a novel concept was

put forth for the application of the technology as developed by ANTECY. Based on this new concept it

was concluded that no technical barriers are foreseen for the implementation of the CO2

sequestration technology. Some questions remain regarding kinetics and full process integration, so

a demo is advocated.

Hydrogen generation

The concept of water splitting into hydrogen and oxygen by electrolysis has been known for over two

hundred years since the first experiments by William Nicholson and Anthony Carlisle around 1800.

While the technology is close to technical maturity, significant improvements in the economics of the

large scale application are still expected. For the technical feasibility no problems are foreseen, for

the economic evaluation of the solar fuels process, the current state of the art is used, with the side

note that great improvement is expected over the coming years. Appendix III: projected cost of PV

and green hydrogen presents the base case and more aggressive scenarios we used for costs of

electrolyser CAPEX and corresponding costs of hydrogen up to 2050.

Methanol synthesis

Methanol synthesis by CO2 hydrogenation, or, alternatively, by CO2 reduction to CO by RWGS

(Reverse Water Gas Shift), followed by CO hydrogenation, are both applied by industry already9.

Commercial catalysts and reactor designs are available for both routes. Selectivity and activity are

comparable for both routes. Tests with commercially available catalysts have been carried out by

ANTECY, achieving selectivity of 99,5%, at an estimated conversion of 25-30% per pass, and activity

of 6 mmol MeOH/g cat/hr. For the solar fuels process, the direct hydrogenation of CO2 is deemed

most feasible. The technology is currently mature enough to be applied in the solar fuels process

without foreseen technical barriers.

5.2 Economic evaluation For each of the main components, cost estimates were obtained. These were used for a CAPEX

estimate. This was done for a 5 MW size installation. Subsequently, scale up rules were applied to

9 Direct CO2 hydrogenation is, for example, done by Mitsui chemicals in a 100 ton/year pilot, constructed in

2008. The more classical route via syngas through RWGS is, for example, done by Audi with plant operator Sunfire in Dresden.

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estimate the CAPEX of a 500 MW size installation. The details of the economic evaluation can be

found in Appendix I: detailed cost estimate of the 5 MW case and Appendix II: detailed cost estimate

of the 500 MW case. The economic evaluation was done for a 25 year lifetime of the plant, with

different discount rates. The results of the economic evaluation, as projected at the current level of

technological progress, and present day prices, for both the 5 MW and 500 MW case are shown in

the following table. In this table, both the CAPEX, the total cost discounted over 25 years and the

methanol production cost (calculated as total discounted cost / discounted tons of methanol

produced) are shown. Details of the cost estimates can be found in: Appendix I: detailed cost

estimate of the 5 MW case, and: Appendix II: detailed cost estimate of the 500 MW case.

5 MW 500 MW

CAPEX (2015) 14.2 M€ 748 M€

Total discounted cost (10% discount rate) 20.9 M€ 1349 M€

(15% discount rate) 18.6 M€ 1154 M€

Discounted cost / discounted ton methanol

(10% discount rate) 861 €/ton 555 €/ton

(15% discount rate) 1089 €/ton 675 €/ton

6 Future perspective

The two key points for the future perspective of the technology that have been identified are the

future energy cost and the cost of hydrogen production by electrolysis. The cost of electricity

production by PV has been declining steadily for decades. As PV becomes more popular, market

share becomes higher and technological progress continues, this trend is expected to continue, as is

shown in Appendix III: projected cost of PV and green hydrogen. However, the solar fuels technology

can be applied with any (mix of-) electrical energy available. At the moment, depending on location,

bulk industrial energy price is around or below 0,04 €/kWh10. In the Netherlands, current bulk

industrial energy price is 0,017 €/kWh (excluding taxes and tariffs)11. Thus, the assumption of an

energy cost of 0,02 €/kWh as a future bulk energy price seems not unrealistic.

The market for hydrogen production by electrolysis is still not well developed. The learning curve for

the large scale deployment of the technology is yet to be fully mounted. As hydrogen production by

electrolysis is deployed more and more, costs are expected to decline significantly. In optimistic

scenarios the cost could be cut to a third in the next decade, in less optimistic scenarios this would

take 25 years (see Appendix III: projected cost of PV and green hydrogen). Since the hydrogen

production by electrolysis currently constitutes almost 50% of the total investment for the 500 MW

case (360 mln€ of the 748 mln€ total), this is expected to have a very pronounced positive effect on

the economics of the technology over the coming years.

Furthermore, ongoing development of the process by ANTECY will further enhance the viability of

the process. At the current stage of development, the electric energy use of the CO2 separation

process is approx. 5,5 times the theoretical energy required (±2500 kJ/kg needed in the Solar Fuels

process vs 450-500 kJ/kg, depending on conditions, in theory). The total energy use (heat and

10

State energy data system, Energy Information Agency, http://www.eia.gov/state/seds/seds-data-complete.cfm, accessed last on 07-09-2015. 11

Kathleen Jennrich, Katharina Grave, Dr. Barbara Breitschopf, European electricity prices and their components, published by Ecofys Germany, Fraunhofer Institute, and the German Ministry of Economic Affairs and Energy, July 2015.

antecy 14

electricity combined) is about 22 times the theoretical energy requirement for separation. Thus,

there is room for improvement, and an increase of total system efficiency from 50%12 to 60% is

deemed realistic.

To illustrate the effect of the advances in both the technology as well as its components, a future

perspective has been created for the following cases:

Electrolyser cost is reduced by 50%

Process efficiency is increased to 60%

Both electrolyser cost halves and process efficiency is increased to 60%

The result for the 500 MW case is shown in the following table (“discount rate” has been abbreviated

to “d.r.”).

Current Electrolyser cost 50% Process η 0.6 Both

CAPEX (future) 748 M€ 568 M€ 748 M€ 568 M€

Total discounted cost (10% d.r.) 1349 M€ 1175 M€ 1349 M€ 1175 M€

(15% d.r.) 1154 M€ 982 M€ 1154 M€ 982 M€

Discounted cost / discounted ton methanol

(10% d.r.) 555 €/ton 483 €/ton 461 €/ton 402 €/ton

(15% d.r.) 675 €/ton 573 €/ton 561 €/ton 477 €/ton

Another aspect that can be considered for the future application is the possible value of CO2 taxation.

The effect of a CO2 tax of 40 and 80€/ton on the process economics is presented below:

Current CO2 tax at 40 €/ton CO2 tax at 80 €/ton

CAPEX 748 M€ 748 M€ 748 M€

Total discounted cost (10% d.r.) 1349 M€ 1349 M€ 1349 M€

(15% d.r.) 1154 M€ 1154 M€ 1154 M€

Discounted cost / discounted ton methanol

(10% d.r.) 555 €/ton 500 €/ton 445 €/ton

(15% d.r.) 675 €/ton 620 €/ton 565 €/ton

In Figure 6 the different possible scenarios (advances in technology and CO2 taxation) are calculated

for different combinations of possible cases. The following scenarios are depicted (in order of

decreasing net production cost):

2015: 1 - The situation as is

2020: 2 - CO2 taxation at 40 €/ton

3 - Process η to 60%

2030: 4 - Electrolyser cost halves and CO2 taxation at 40 €/ton

5 - Electrolyser cost halves and CO2 taxation at 80 €/ton

12

Process efficiency is defined here as the ratio between chemical energy in the product and total electric energy into the process. The current design is evaluated to have an efficiency of approximately 50%.

antecy 15

6 - Process η to 60% and CO2 taxation at 40 €/ton

7 - Process η to 60% and CO2 taxation at 80 €/ton

8 - Electrolyser cost halves and CO2 and Process η to 60%

2040: 9 - Electrolyser cost halves and CO2 taxation at 40 €/ton

10 - Electrolyser cost halves and CO2 and Process η to 60% and CO2 taxation at 40 €/ton

11 - Electrolyser cost halves and CO2 and Process η to 60% and CO2 taxation at 80 €/ton

From the graph it can be seen that the dependence on discount rate is heavy, which is caused by the

process being very capital intense. However, most scenarios predict that, at a discount rate of 10%, it

will be possible to produce methanol for a competitive price. An added effect, which was not taken

into account in this calculation is the price evolution of commercial methanol, beyond inflation,

which is likely to have an additional positive effect on the competitiveness of the Solar Fuels process.

This is shown in Figure 7. The projected methanol price is based on the calculation shown with Figure

10 (5% yearly), but removing the effect of inflation (a yearly price increase of 2.5% is used).

Figure 6, Current and future cost of methanol production.

1

3

2

6 5

8

4

7 10

11

9

1

3

2

6 5

8

4

7

10

11

9

200

250

300

350

400

450

500

550

600

650

700

2015 2020 2025 2030 2035 2040

Dis

cou

nte

d c

ost

/dis

cou

nte

d t

on

(€

/to

n)

Year of implementation

Future discounted cost/discounted ton

10% discount rate

15% discount rate

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Figure 7, Current and future cost of methanol production compared to projected methanol price.

In Figure 8 the future cost of methanol calculated in barrel oil equivalent (on energy basis) is

displayed.

Figure 8, Current and future product cost per Barrel of Oil Equivalent.

200

250

300

350

400

450

500

550

600

650

700

2015 2020 2025 2030 2035 2040

Dis

cou

nte

d c

ost

/dis

cou

nte

d t

on

(€

/to

n)

Year of implementation

Future discounted cost/discounted ton

Conservative 10%

Optimistic 10%

Conservative 15%

Optimistic 15%

Projected methanol price

50.00

70.00

90.00

110.00

130.00

150.00

170.00

190.00

210.00

2015 2020 2025 2030 2035 2040

Co

st/B

OE

(€/B

OE)

Year of implementation

Cost/BOE

Conservative 10%

Optimistic 10%

Conservative 15%

Optimistic 15%

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Appendix I: detailed cost estimate of the 5 MW case

CO2 capture

Of the process the CO2 production has undergone the most developed efforts by ANTECY and the

concept that is calculated in this document is as follows:

During the meeting of 29-01-2015 a concept was discussed for the adsorption of CO2 from air,

whereby the solid adsorbing particles move through a bed that is flushed in counter flow with air.

Upon exiting the bed, the particles are transported to a vacuum desorption reactor, where the CO2 is

stripped and thereby the particles regenerated. The particles are then returned to the bed, where

CO2 adsorption recommences. This approach has economic benefits, as it minimizes the number of

vacuum vessels needed. During the meeting of 20-03-2015, a modification of this concept was

discussed, whereby the bed does not move during adsorption, and an extra bed is installed. The beds

are flushed with air until they are saturated. The saturated sorbent is then moved into a desorber,

and filled with regenerated adsorbent from the same desorber. By staggering the loading and

regenerating of the different adsorbers, one bed is filled/emptied while the others are being flushed

with air. In this way, the desorber is in continuous use, desorbing the sorbent from one adsorber at a

time.

The global operational parameters of the system were calculated for different parameter choices,

based on this calculation the following case was chosen:

Adsorber:

Bed height: 0.5 m

Adsorber diameter: 20 m

Particle size: 5 mm

Number of adsorbers: 5

Desorber:

Height: 10 m

Diameter: 3.8 m

Assumptions

The solid particles used for the CO2 adsorption are assumed to:

Be free flowing

Be attrition resistant

Have a CO2 adsorption capacity of 10 Nm3 CO2 per m3 of sorbent bed

antecy 18

Concept schematic

Figure 9: Concept schematic (side view of one adsorber and one desorber)

6.1 Estimation of CAPEX of CO2 sequestration step The CO2 adsorbers are a part that will be custom made for this process. As far as possible, off the

shelf parts will be used for the units. To estimate the cost of the vessels an estimate by mass is made

by calculating size of various parts and components. To estimate cost of desorbers, the minimum

wall thickness is calculated

Desorber wall thickness

Calculation of vacuum vessel wall thickness according to ASME VIII Div I Sec A UG-2813: Thickness of

shells and tubes under external pressure (units are inches, psi etc.).

Symbols used:

A = factor determined from chart G in ASME SECTION II PART D14 and used to enter the applicable

material chart in ASME SECTION II PART D.

B = factor obtained from applicable material chart from ASME SECTION II PART D

Do = outside diameter of vessel

E = elasticity modulus at (maximum) design temperature

L = total length of the vessel

P = external pressure (for full vacuum P = 15 psi)

Pa = calculated maximum allowable external pressure

t = vessel wall thickness

13

Part UG, General requirements for all methods of construction and all materials (REFC01) 14

2007 ASME boiler and pressure vessel code, II part D, Properties (Customary) Materials (REFC02)

antecy 19

For the CO2 adsorption vessels the following values are used:

Do = 523 cm

t = 17.3 mm

L = 759 cm

This makes L/D0 = 1.45 and D0/t = 303. Using these values it is found from chart G in ASME SECTION II

PART D, that A = 0.000175. Using the chart for carbon or low alloy steel (fig CS-1 in ASME SECTION II

PART D) the value the maximum allowable external pressure is calculated using:

𝑃𝑎 =2𝐴𝐸

3(𝐷𝑜𝑡

)

For the obtained values of A, D0 and t, and using E = 29e6 (up to 300 F), this gives a Pa of 11.2 psi.

Price per desorber

At a wall thickness of 20 mm, the total volume of steel required for the construction of a vessel of the

dimensions given equals:

Cylinder:

𝑉𝑐 = 𝐿 ∙ 𝑝𝑖 ∙ (𝐷𝑜

2

4−

(𝐷𝑜 − 2𝑡)2

4) = 7.59 ∙ 3.141 ∙ (

5.232

4−

(5.23 − 0.0134)2

4) = 2.15 𝑚3

Top & bottom (together one complete sphere):

𝑉𝑠 =4

3𝑝𝑖 ∙ (

𝐷𝑜3

8−

(𝐷𝑜 − 2𝑡)3

8) = 1.48 𝑚3

𝑉𝑡 = 𝑉𝑐 + 𝑉𝑠 = 3.63 𝑚3

The mass per adsorber comes to (using 7800 kg/m3), 28673 kg.

antecy 20

At a steel price of 1.5 €/kg15, the cost per vessel comes to 1.5*28673 = 43000 €.

Cost of adsorbing material

Total volume needed for 5 MW system is 5 times 0,5 m bed, 20 m diameter, equals 785 m3 sorbent.

Density assumed to be approx. 400 kg/m3, require 314 tons. Assuming price of 2 €/kg, cost is 628 k€.

Blowers

To calculate the pressure drop in the adsorber bed, the Ergun equation is used.

With:

µ = fluid viscocity (dynamic), used is 1.85·10-5 kg/ms.

ε = Void fraction. For a poured random packing of spheres this is 0.375-0.391, for a close random

packing this is 0.359-0.375. Used is 0.375.

Dp = particle diameter, varied between 0.5 and 15 mm.

L = bed height (HA in Figure 9), varied from 0.1 to 3 m.

ρ = fluid density, used is 1.29 kg/m3.

vs = superficial velocity, follows from chosen residence time and bed height.

The chosen parameter values for number of adsorbers and adsorber size determine the residence time. This in turn, together with the chosen particle size determines the pressure drop across the adsorber. Using: µ = 1.85·10-5 kg/ms.

ε = 0.375 -

Dp = 5 mm.

L = 0.5 m

ρ = 1.29 kg/m3.

vs = superficial velocity, follows from chosen residence time and bed height and required airflow, for

the 5 MW case this is 0.32 m/s.

This results in a pressure drop of 400 Pa.

Canada blower has a price list available for centrifugal fans of various sizes (REFC05) (though admittedly not the most energy efficient alternative). The total flow required is 402 m3/s or roughly 850000 SCFM. The largest blowers available delivers a flow of 80000 SCFM, requiring 11 total. The

15

Breeveld staal prijslijst 29-01-2014 (REFC03)

antecy 21

price quoted on the site of Canada blower for this type of fan is roughly 28950 USD (depending on the required head). This brings the cost estimation for the blowers to 318 kUSD or 236 k€. To account for the fact that more energy efficient blowers will be more expensive, but also more economical on the whole, a cost estimation of 300 k€ is used.

Vacuum pump

The concept is to flush the sorbent with dry steam to displace any air in the adsorber. At 20 oC, this

requires a pressure of 25 mbar. In order to displace the air in the reactor with steam, it is assumed

that a volume of dry steam of twice the volume of the reactor is required (more is unlikely to be

prudent, since the absence of CO2 during evacuation will start to cause CO2 to desorb). The flow

required to achieve this is 717 m3/hr.

Additionally, a flow of steam is needed to transport the produced CO2 from the reactor (lowering the

CO2 concentration, allowing more CO2 to be released). The pressure of this flow can be much higher,

since the adsorber will be heated to release the CO2. In order to calculate the flow of steam needed

for this, data from16 is used (specifically, the temperature dependent Gibbs free energy change of

reaction is obtained).

The reaction taking place is:

𝐶𝑂2(𝑔) + 𝐾2𝐶𝑂3 ∙ 1.5𝐻2𝑂(𝑠) ↔ 2𝐾𝐻𝐶𝑂3(𝑠) + 0.5𝐻2𝑂(𝑔)

For any general reaction 𝛼𝐴 + 𝛽𝐵 → 𝜎𝑆 + 𝜏𝑇 it can be said that 𝐾𝑐 =[𝑆]𝜎[𝑇]𝜏

[𝐴]𝛼[𝐵]𝛽. So, in this case:

𝐾𝑐 =√[𝐻2𝑂]

[𝐶𝑂2]

Using ∆𝑟𝐺𝑜 = −𝑅𝑇𝑙𝑛(𝐾) and rewriting, the equilibrium concentration of CO2 can be calculated for a

given concentration of water vapour. The Gibbs free energy of reaction is taken from figure 6 of16 to

be:

∆𝐺 = 88.033 ∙ 𝑇 − 39230

Assuming the reactor is heated to 80oC. The saturation pressure of water at this temperature is

calculated (as before) using the Antoine equation:

𝑙𝑜𝑔10(𝑃) = 𝐴 −𝐵

𝐶 + 𝑇

With A=10.196; B=1730.63 and C=-39,724. (P in Pa and T in K).

For T=353 K, this gives 47 kPa or 0.47 bar. This is thus the highest concentration of water vapour

possible at this temperature without condensation. However, to achieve such a concentration, a

significant amount of heat is needed to generate this water. Thus, a tradeoff can be made between

desorption pressure (energy use of and size of vacuum pump) and heat use. At a vapour pressure of

0.2 bar and a temperature of 80 oC, the equilibrium concentration of CO2 is 0.028 bar. Thus, at this

pressure a flow with a composition 12.3% CO2 and 87.7% H2O and a total pressure of 0.228 bar is

16

Ab Initio Thermodynamic Study of the CO2 Capture Properties of Potassium Carbonate Sesquihydrate, K2CO3·1.5H2O; Yuhua Duan et al; The Journal of Physical Chemistry C 2012 116 (27), 14461-14470 (REFC07)

antecy 22

produced. The heat required to evaporate this flow of water is less than the heat generated by the

hydrogen electrolyser (850 kW of heat needed, more than 1 MW of heat generated).

The total flow that needs to pumped by the vacuum pump in this case is approx 12600 m3/hr, but at

a pressure of 0.228 bar.

A quote was obtained from Pfeiffer vacuum for a pumping station that can pump 35000 m3/hr at a

pressure of 25 mbar. This unit is (at least) three times as big as required, but additionally the data

provided assumes it operates at 25 bar. To get an idea of the change of energy use at higher

operating pressure, REFC0817 is used (datasheet to a different vacuum pump). In the graphs in this

datasheet it can be seen that in the range of 25mbar to 0.228 bar, the flow rate at constant power is

either constant or increasing with increasing pressure.

The price of the Pfeiffer system is 695 k€, and this system is three times too big, and capable of

operating continuously at a too deep vacuum. For this reason an estimate of 50 k€ is used.

Adsorber

To estimate the cost of the adsorbers, a breakdown into likely parts was made. These are:

- Fine mesh (1-2mm) stainless steel gauze to support the sorbent

- Course mesh zinc coated steel grate (30-60 mm) to support gauze

- Sides (1m high)

- Cover, corrugated roofing sheets (bitumen)

- Steel structure to support the grate/sides/roof

- Main valve

- Filling system

Fine mesh (1-2mm) stainless steel gauze to support the sorbent

1545.34 m2 € 3.41 €/m2 € 5,263.87

Course mesh zinc coated steel grate (30-60mm) to support gauze

1545.34 m2 € 1.50 €/kg € 2,318.01

Sides (1m high) 7525.78 kg € 1.35 €/kg € 10,159.81

Cover, corrugated roofing sheets (bitumen) 2231.38 m2 € 4.00 €/m2 € 8,925.51

Steel structure to support the grate/sides/roof 1967.59 m € 50.00 €/m € 98,379.31

6.2 Estimation of CAPEX of hydrogen production by electrolysis

Hydrogen electrolyser

Not many manufacturers of electrolyzers are active around the world. The simple reason is that for

nearly all applications the cost of hydrogen is lower if bought directly in bottles, skids, tanks or

pipelines and for high volume consumption applications production is cheapest from natural gas. So,

the market for electrolyzers is limited.

17

Datasheet EU 1000 - EU 1000/B from Agilent technologies (REFC08)

antecy 23

Hgenerators.com has a list on their website with prices for various sizes of electrolyzers (REFH01):

Adjustable Rates / Model

H2O consumed ml/hour

kWh consumed per hour

H2 gas produced

ml/min

H2 gas produced liters/hour

H2 gas produced cubic meters/hour

Affordable Price:

LM-200 10 0.1 200 12 0.012 $4,995

LM-300 15 0.15 300 18 0.018 $5,995

LM-500 25 0.25 500 30 0.03 $6,595

LM-1000 50 0.5 1000 60 0.06 $9,895

LM-2000 100 1 2000 120 0.12 $14,295

LM-3000 150 1.5 3000 180 0.18 $17,595

LM-5000 250 2.5 5000 300 0.3 $23,095

LM-10000 500 5 10000 600 0.6 $42,895

LM-20000 1000 10 20000 1200 1.2 $85,795

LM-30000 1500 15 30000 1800 1.8 $128,685

LM-60000 3000 30 60000 3600 3.6 $257,995

HG-50 41667 215 833333 50000 50 $398,995

HG-100 83334 430 1.6MM 100000 100 $598,995

HG-200 166668 860 3.3MM 200000 200 $798,995

From these prices a price per m3H2/hr capacity can be calculated. These values can be plotted as

datapoints to find the relation between size and price for electrolyzers.

It can be seen that the price per m3H2/hr converges to around 4000 USD per m3/hr installed for large

units. The base calculation case uses roughly 900 m3/hr, which is thus estimated at 3.6 mlnUSD

(2.67 mln€). It can be expected that the cost for hydrogen can further decrease in the future, when

larger installations are built.

Hydrogen electrolyzer, calculation method #2

Since hydrogen production by electrolyzer is not a technology that is widely used: for small scale

applications hydrogen procurement in bottles or trucks is generally more economical, for large scale

applications the same applies for production from natural gas. The Chlor-alkali process on the other

y = 56216x-0.443

0

50000

100000

150000

200000

250000

300000

350000

400000

450000

0.01 0.1 1 10 100 1000

Pri

ce (

USD

) p

er

m3/h

r

Unit size (m3/hr)

Reeks1

Fit (power)

antecy 24

hand, is widespread and applied on kton/year scale all over the world. The electrolyzers used in this

process are not fundamentally different from hydrogen electrolyzers, thus calculating the cost of

such an electrolyzer for hydrogen production may be insightful for large scale hydrogen production.

From18 it is found that for a 160.000 Mton/year chlor-alkali plant, the cost breakdown is as follows:

Item Estimated investment in kUS$

Cells 27,200

Brine purification 14,000

Chlorine processing 16,000

Waste gas treatment 2,300

Caustic evaporation 6,900

Utilities 4,500

Rectifiers 10,000

Engineering 10,000

Total 90,900

Thus, the cost of the electrolysis cells is 27,2 mln USD. The hydrogen production of a

160.000 Mton/yr chlorine plant is 55 mln m3H2/yr or 6,3·103 m3H2/hr. This brings the cost per m3/hr

installed to 4334 USD per m3/hr installed, nearly identical to the previous analysis.

A further conclusion of this analysis is that, at the moment, economics of production scale do not

apply to electrolyzers. This was included in the scale up calculation.

6.3 Estimation of CAPEX of methanol synthesis

Hydrogen compressor

Most commercial hydrogen electrolyzers produce hydrogen at elevated pressure, but rarely above

10barg. For this reason a compressor is needed to compress the produced hydrogen further to at

least 50 barg. To estimate the cost of a the hydrogen compressor a quote from RixIndustries was

obtained. This compressor is rated at 750 SQFM (1275 m3/hr), with suction at 110 psig (7.5 barg) and

discharge at 900 psig (62 barg). This is somewhat higher than needed (required is approx. 1000 m3/hr

at 50 bar). The price quoted is 375 kUSD, or 280 k€. This is not likely to be the cheapest or best

option, but will serve for calculation and estimation purposes.

CO2 compressor

In principle the compressor selected for calculation for compression of hydrogen is large enough to

compress both the CO2 and hydrogen at the same time. However, the CO2 is produced at

atmospheric pressure, so the pressure needs either to be lifted to 7,5 barg when mixing with

hydrogen is done before the hydrogen compressor, or compressed to 50 barg when mixing with

hydrogen is done after the hydrogen compressor. In either way, the flow of CO2 is one third of the

hydrogen flow, and CO2 is an easier gas to compress (both mechanically in terms of leak tightness

and combustibility as well as thermodynamically). For this reason the cost for the additional CO2

compressor is estimated at just over one third of the cost of the hydrogen compressor, at 100k€.

18

Supramaniam Srinivasan, “Fuel cells: From Fundamentals to Applications”, ISBN-10: 0-387-25116-2, 2006 Springer, table 3,7 on page 114

antecy 25

Methanol reactor

The methanol reactor will be built under license modelled on known and tested blueprints. To

estimate the costs of this part, the George Olah methanol plant in Iceland is used as a reference. The

technology used in this plant is almost identical to what is being developed by ANTECY (with the

main exception that ANTECY has the capability to obtain CO2 from air). The size of the Iceland plant is

also neigh on the same as the base calculation case of ANTECY. According to literature (REFM02) this

plant was developed at a cost of 6mln€ (8 mln USD). Applying the reverse calculation for cost for

Connections, Engineering and Startup, this price would imply that the total cost of the plant’s

hardware was 4mln€. Within this 4mln there is the cost for hydrogen electrolyzers (3 mln€),

hydrogen compressors (275 k€), CO2 compressors (100 k€), leaving 600 k€ for the methanol reactor

& distiller.

Alternatively one could look at the cost of a large methanol plant. Off course the technology for this

type of plant is somewhat different from what is being proposed by ANTECY (conventional methanol

production is done from methane/NG). According to REFM01, a 5000 ton/day methanol plant costs

480 mln USD to build. Again removing the cost for Connections, Engineering and Startup, this leaves

a hardware total of 320 mln USD. A plant of this size is roughly 550 times bigger than the base

calculation case for ANTECY. Dividing the cost of 320 mln USD by 550 directly gives a cost for a

methanol plant of 580 kUSD or 435 k€, including the hydrogen compressors and CO2 compressors.

This means that the cost estimated through the George Olah comparison of 1 mln€ is significantly

higher. However, a straight division is not likely to give an accurate result since there is both a

difference in technology as well as a significant difference in size (which leads to economics of scale

differences). In spite of this, the calculation does indicate that the price estimate through the

comparison with the George Olah plant yields a credible result.

6.4 Total main equipment cost Of the costs estimated, the hydrogen electrolyzer constitutes the bulk of the costs. The new concept

(multiple large adsorbers coupled to two desorbers) reduces the cost main equipment of the CO2

capture by roughly 40% (from 2,85 mln€ to 1,7 mln€). It is also expected to greatly reduce the cost of

valves, piping and electronics/data acquisition and control hardware and.

Item Cost (k€)

CO2 adsorption

Desorbers (2) 86

Vacuum pump 50

Adsorbers (5) 125

Sorbent 628

Blower 300

Total CO2 adsorption 1189

H2 generation

Electrolyzer 2667

Total H2 generation 2667

Methanol synthesis

Hydrogen compressor 280

CO2 compressor 100

Reactor 600

Total Methanol synthesis 980

Total hardware 4836

antecy 26

6.5 Real construction cost The cost of main equipment for the 5 MW plant has been estimated at around 5mln€. However, for

many parts, additional cost is required for installation of the equipment. This is only not the case for

the electrolyzer (which is bought as a complete “plug-and-play” unit) and the sorbent (which is just

inventory). For the other parts, a rule of thumb of a factor four is used to install the equipment. This

brings the total battery limit cost of the plant to 9459 k€.

Over the total battery limit cost, a 50% increase is calculated to account for utilities. In the case of

the 5 MW unit, this amounts to 4730 k€. This brings the total cost estimate to 14189 k€.

This is summarized in the following table:

Main equipment cost (k€) Multiplication Battery limit cost (k€)

H2 generator 2667 1.00 2667

H2 compressor 280 4.00 1120

CO2 compressor 100 4.00 400

Reactor 600 4.00 2400

Vacuum pump 50 4.00 200

Blower 300 4.00 1200

CO2 capture unit 125 4.00 500

Desorber tank 86 4.00 344

Sorbent 628 1.00 628

Battery limit total 9459

Utilities 0.5 4730

Total 14189

6.6 Discounting cost To get a realistic ideal for the economic feasibility of the concept, the Net Present Value is calculated

over a 25 year period, with various discounting rates. The following assumptions are made:

The investment of the construction of the plant is done over two years: two thirds of the

investment is made in year one, one third in year two.

Production starts in year two, with half production that year. Full production is assumed for

years three and beyond.

The plant runs year round, on average, at 80% capacity.

Operational cost (excluding energy cost) is estimated at 100 k€ per year for year three and

beyond, with a 2% rise per year to account for inflation.

Energy costs are assumed constant at 0,02 €/kWh.

Methanol value is assumed to be 397 €/ton in year one, and increased by 5% per year to

account for inflation and increased scarcity of fossil raw materials (the validity of this

assumption is verified in Figure 10, the 5% per year increase line is shown in red).

antecy 27

Figure 10: The historical evolution of methanol price

The result can be used to calculate a cost of production of methanol through the solar fuels process,

and compare this to the projected methanol price. The calculation is done by dividing the discounted

kg’s produced over the 25 year period by the discounted total cost over the same period. In the

following table, it can be seen that the discounted cost per discounted kg are 0.66 €/kg and 0.86 €/kg

respectively for 5% and 10% discount rates. So, it can be concluded that, the 5 MW plant would not

be competitive with current methanol sources (but this would not be the purpose of the 5 MW

plant).

€ 0

€ 100

€ 200

€ 300

€ 400

€ 500

€ 600

apr-01 jan-04 okt-06 jul-09 apr-12 dec-14

His

tori

cal M

eth

ano

l pri

ce (

€/t

on

)

Date

antecy 28

Year Capital cost Fixed operational cost Energy cost CO2 tax Total cost Production (kg) 1 € 9.47 M € 50.0 k € .0 k € - € 9.52 M 0 2 € 4.73 M € 50.0 k € 359.93 k € - € 5.14 M 1425693 3 € - € 100.0 k € 719.86 k € - € 819.86 k 2851386 4 € - € 102.0 k € 719.86 k € - € 821.86 k 2851386 5 € - € 104.04 k € 719.86 k € - € 823.90 k 2851386 6 € - € 106.12 k € 719.86 k € - € 825.98 k 2851386 7 € - € 108.24 k € 719.86 k € - € 828.10 k 2851386 8 € - € 110.41 k € 719.86 k € - € 830.27 k 2851386 9 € - € 112.62 k € 719.86 k € - € 832.48 k 2851386 10 € - € 114.87 k € 719.86 k € - € 834.73 k 2851386 11 € - € 117.17 k € 719.86 k € - € 837.03 k 2851386 12 € - € 119.51 k € 719.86 k € - € 839.37 k 2851386 13 € - € 121.90 k € 719.86 k € - € 841.76 k 2851386 14 € - € 124.34 k € 719.86 k € - € 844.20 k 2851386 15 € - € 126.82 k € 719.86 k € - € 846.69 k 2851386 16 € - € 129.36 k € 719.86 k € - € 849.22 k 2851386 17 € - € 131.95 k € 719.86 k € - € 851.81 k 2851386 18 € - € 134.59 k € 719.86 k € - € 854.45 k 2851386 19 € - € 137.28 k € 719.86 k € - € 857.14 k 2851386 20 € - € 140.02 k € 719.86 k € - € 859.89 k 2851386 21 € - € 142.82 k € 719.86 k € - € 862.69 k 2851386 22 € - € 145.68 k € 719.86 k € - € 865.54 k 2851386 23 € - € 148.59 k € 719.86 k € - € 868.46 k 2851386 24 € - € 151.57 k € 719.86 k € - € 871.43 k 2851386 25 € - € 154.60 k € 719.86 k € - € 874.46 k 2851386 Discounted costs per discouted kg Sum € 14.20 M € 2.98 M € 16.92 M € 34.10 M 67007581.54 € 0.509 Discount rate 5% € 13.97 M € 1.64 M € 9.59 M € 25.21 M 37987457.15 € 0.664 Discount rate 10% € 13.77 M € 1.03 M € 6.14 M € 20.94 M 24322892.59 € 0.861 Discount rate 15% € 13.58 M € 720.0 k € 4.32 M € 18.62 M 17105435.48 € 1.089

5 MW: base case

antecy 29

Appendix II: detailed cost estimate of the 500 MW case

In order to evaluate the effect of scale up on the economics of the process, rules of thumb were used

to calculate the cost of the process upscaled to 500 MW. In order to come to a realistic rule of

thumb, the data in a cost estimation article19 of the cost of CO2 sequestration by an amine system is

used as a reference. The article calculates a 600 MEe coal power plant. At 820 gCO2/kWh, 7500 hours

per year and 90% capture rate, this is 3,32e6 ton CO2/year. Our 5 MW case sequestrates 3,8e3

ton/year, so our 5 MW case is approximately 850 times smaller.

A flat multiplication of two comparable parts: the blower and the CO2 compressor show that this

highly overestimates the costs. The 5 MW case CO2 compressor investment cost, 400 k€, multiplied

by 850, gives 340 mln€. Cost cited in19 is 31,73 mln€. The 5 MW case blower is estimated at 30 k€ (for

the flue gas case), times 850 gives 25,5 mln€. The cited cost is 3,1 mln€.

Alternatively, one could use a multiplication to the power 0.66. This gives, both for the blower and

compressor a much more accurate result (34,3mln€ and 2.6mln€ respectively). So, for these parts, as

well as the H2 compressor, methanol reactor and vacuum pump, this calculation is used. For the

electrolyzer the benefit of scale up is expected to be less pronounced, so a cost reduction of 10% is

applied (cost multiplied by 90 instead of 100). For the cost of desorption vessels, adsorption vessels

and sorbent a flat multiplication is used. This yields the following result:

5 MW Battery limit cost (k€)

Scale up 500 MW cost estimate (k€)

H2 generator 2667 x90 240030

H2 compressor 1120 A*x^0,66 23400

CO2 compressor 400 A*x^0,66 8357

Reactor 2400 A*x^0,66 50143

Vacuum pump 200 A*x^0,66 4179

Blower 1200 A*x^0,66 25072

CO2 capture unit 500 x100 50000

Desorber tank 344 x100 34400

Sorbent 628 x100 62800

Battery limit total 9459

498381

Utilities 4730 249191

Total 14189

747572

Using this cost estimate, the cost of producing methanol can be estimated, similarly to was done for

the 5 MW case. The discounted cost per discounted kg are 0.489 €/kg and 0.60 €/kg respectively for

5% and 10% discount rates.

19

Abu-Zahra et.al. Int.Journ. of Greenhouse Gas Control I, (2007) 135-142

antecy 30

Year Capital cost Fixed operational cost Energy cost CO2 tax Total cost Production (kg) 1 € 498.67 M € 500.0 k € - € - € 499.17 M 0 2 € 249.33 M € 500.0 k € 35.99 M € - € 285.83 M 142569322 3 € - € 1.0 M € 71.99 M € - € 72.99 M 285138645 4 € - € 1.02 M € 71.99 M € - € 73.01 M 285138645 5 € - € 1.04 M € 71.99 M € - € 73.03 M 285138645 6 € - € 1.06 M € 71.99 M € - € 73.05 M 285138645 7 € - € 1.08 M € 71.99 M € - € 73.07 M 285138645 8 € - € 1.10 M € 71.99 M € - € 73.09 M 285138645 9 € - € 1.13 M € 71.99 M € - € 73.11 M 285138645 10 € - € 1.15 M € 71.99 M € - € 73.13 M 285138645 11 € - € 1.17 M € 71.99 M € - € 73.16 M 285138645 12 € - € 1.20 M € 71.99 M € - € 73.18 M 285138645 13 € - € 1.22 M € 71.99 M € - € 73.21 M 285138645 14 € - € 1.24 M € 71.99 M € - € 73.23 M 285138645 15 € - € 1.27 M € 71.99 M € - € 73.25 M 285138645 16 € - € 1.29 M € 71.99 M € - € 73.28 M 285138645 17 € - € 1.32 M € 71.99 M € - € 73.31 M 285138645 18 € - € 1.35 M € 71.99 M € - € 73.33 M 285138645 19 € - € 1.37 M € 71.99 M € - € 73.36 M 285138645 20 € - € 1.40 M € 71.99 M € - € 73.39 M 285138645 21 € - € 1.43 M € 71.99 M € - € 73.41 M 285138645 22 € - € 1.46 M € 71.99 M € - € 73.44 M 285138645 23 € - € 1.49 M € 71.99 M € - € 73.47 M 285138645 24 € - € 1.52 M € 71.99 M € - € 73.50 M 285138645 25 € - € 1.55 M € 71.99 M € - € 73.53 M 285138645 Discounted costs per discouted kg Sum € 748.0 M € 29.84 M € 1691.68 M € 2469.52 M 6700758154 € 0.369 Discount rate 5% € 736.13 M € 16.42 M € 959.03 M € 1711.58 M 3798745715 € 0.451 Discount rate 10% € 725.33 M € 10.32 M € 614.06 M € 1349.71 M 2432289259 € 0.555 Discount rate 15% € 715.48 M € 7.20 M € 431.84 M € 1154.52 M 1710543548 € 0.675

500 MW: base case

antecy 31

Year Capital cost Fixed operational cost Energy cost CO2 tax Total cost Production (kg) 1 € 378.67 M € 500.0 k € - € - € 379.17 M 0 2 € 189.33 M € 500.0 k € 35.99 M € 18.86 M € 206.96 M 171493956 3 € - € 1.0 M € 71.99 M € 37.73 M € 35.26 M 342987912 4 € - € 1.02 M € 71.99 M € 37.73 M € 35.28 M 342987912 5 € - € 1.04 M € 71.99 M € 37.73 M € 35.30 M 342987912 6 € - € 1.06 M € 71.99 M € 37.73 M € 35.32 M 342987912 7 € - € 1.08 M € 71.99 M € 37.73 M € 35.34 M 342987912 8 € - € 1.10 M € 71.99 M € 37.73 M € 35.36 M 342987912 9 € - € 1.13 M € 71.99 M € 37.73 M € 35.38 M 342987912 10 € - € 1.15 M € 71.99 M € 37.73 M € 35.41 M 342987912 11 € - € 1.17 M € 71.99 M € 37.73 M € 35.43 M 342987912 12 € - € 1.20 M € 71.99 M € 37.73 M € 35.45 M 342987912 13 € - € 1.22 M € 71.99 M € 37.73 M € 35.48 M 342987912 14 € - € 1.24 M € 71.99 M € 37.73 M € 35.50 M 342987912 15 € - € 1.27 M € 71.99 M € 37.73 M € 35.53 M 342987912 16 € - € 1.29 M € 71.99 M € 37.73 M € 35.55 M 342987912 17 € - € 1.32 M € 71.99 M € 37.73 M € 35.58 M 342987912 18 € - € 1.35 M € 71.99 M € 37.73 M € 35.60 M 342987912 19 € - € 1.37 M € 71.99 M € 37.73 M € 35.63 M 342987912 20 € - € 1.40 M € 71.99 M € 37.73 M € 35.66 M 342987912 21 € - € 1.43 M € 71.99 M € 37.73 M € 35.69 M 342987912 22 € - € 1.46 M € 71.99 M € 37.73 M € 35.71 M 342987912 23 € - € 1.49 M € 71.99 M € 37.73 M € 35.74 M 342987912 24 € - € 1.52 M € 71.99 M € 37.73 M € 35.77 M 342987912 25 € - € 1.55 M € 71.99 M € 37.73 M € 35.80 M 342987912 Discounted costs per discouted kg Sum € 568.0 M € 29.84 M € 1691.68 M € 1402.90 M 8060215939 € 0.174 Discount rate 5% € 558.98 M € 16.42 M € 959.03 M € 1031.80 M 4569439764 € 0.226 Discount rate 10% € 550.79 M € 10.32 M € 614.06 M € 853.33 M 2925754997 € 0.292 Discount rate 15% € 543.30 M € 7.20 M € 431.84 M € 756.01 M 2057580658 € 0.367

500 MW: most optimistic

antecy 32

Appendix III: projected cost of PV and green hydrogen

Figure 11. Base case and aggressive scenarios for cost projections of solar PV power, electrolyser CAPEX, and hydrogen.

Figure 11 shows the projected price of PV electricity, electrolyser CAPEX and green hydrogen. The

following assumptions were used:

Net present value is assumed zero at a discount rate of 7%, equivalent to a weighted average

cost of capital of 7%.

32% utilisation of electrolyser.

Electrolyser capacity of 75% of PV DC capacity (to increase electrolyser utilisation).

A solar yield of 23.7% for single axis tracking system in China (includes 10% curtailment of

electricity because of undersized electrolyser) is used to calculate cost of electricity.

Installed costs of electrolyser 1.2 times electrolyser costs.

5% manufacturing margin.

The data presented is the expectation for modular, MW scale units with minimal installation costs.

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Green H2 costs scenarios Fossil H2 $/kg

LNG based, 12$/mmBTU, LCOE $c/kWh

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green H2, Base $/kg

green H2, Aggressive $/kg

PV electricity, Base $c/kWh

PV electricity, Aggressive $c/kWh

Electrolyser Capex, Base $/kW

Electrolyser Capex, Aggressive $/kW