innovation case study: photovoltaicsec.europa.eu/environment/enveco/pdf/paper4.pdfdraft - not to be...

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INNOVATION CASE STUDY: PHOTOVOLTAICS

Assessing Innovation Dynamics Induced By Environment Policy Framework Contract No Env.G.1/Fra/2004/0081

Authors: Jason Anderson Samuela Bassi

Emilia Stantcheva Patrick ten Brink

DRAFT

15 JUNE 2006


1 INTRODUCTION ................................................................................................3

2 PHOTOVOLTAIC TECHNOLOGY.................................................................4

2.1 What are photovoltaics?...................................................................................4

2.2 What are the benefits and drawbacks of PV?................................................6

3 INNOVATION IN THE CONTEXT OF PV .....................................................9

3.1 What are the indicators of innovation? ..........................................................9

3.2 Current cost of PV systems ..............................................................................9

3.3 The future: price per area and performance per area; the differential importance of manufacturing costs and efficiency .................................................12

3.4 Experience Curves ..........................................................................................14 3.4.1 Expectations on future PV costs................................................................16 3.4.2 The nature of experience and learning ......................................................17 3.4.3 Conclusions about learning .......................................................................19

4 POLICY SUPPORT FOR PV ...........................................................................21

4.1 The context ......................................................................................................21

4.2 European policy ..............................................................................................21

4.3 National policy instruments ...........................................................................22

4.4 What are the merits of the existing policy instruments?.............................23

4.5 How do the policy instruments affect innovation?.......................................24 4.5.1 Germany ....................................................................................................24 4.5.2 Japan ..........................................................................................................26 4.5.3 UK .............................................................................................................27 Comparing the innovation outcomes of national policy instruments ...............28 4.5.4..........................................................................................................................28

4.6 The link between market penetration and innovation ................................31


1 INTRODUCTION

Providing clean, reliable energy is a major goal for policymakers and concerned individuals worldwide. The unfortunate fact is that the cheapest energy sources, with a century of technical and infrastructure development backing them, are polluting fossil fuels. Thus when a technology like solar photovoltaics comes along – converting the sun’s rays to electricity with no moving parts, no pollution, and no fuel costs – the excitement is understandable. But the environment as a reason for technological and market development is a relatively new concept – while there are examples of successful transitions in the past in discrete areas (unleaded fuels, non-phosphorous detergents, flue gas desulphurisation), changing the world’s largest and most entrenched industrial system, energy provision, is a massive challenge. The prevailing notion is that if only we could innovate challengers to fossil fuels to the point that their costs were low enough, and their other advantages obvious enough, to play a major role in energy provision. This paper thus examines innovation in solar photovoltaics in three sections: 1. a description of the technology, 2. innovation in PV, and 3. the impact of supportive policy.


2 PHOTOVOLTAIC TECHNOLOGY

2.1 What are photovoltaics? Photovoltaic (PV) cells produce electricity directly when exposed to sunlight. This property has made them invaluable in applications where other sources of energy are hard to access, such as their original use in satellites, but also in remote applications like telecommunications repeater stations and off-grid homes. Given the abundance and free availability of sunlight, expanding into much broader use is long been an attractive prospect. However, there are technical challenges to overcome in bringing costs down to the point where this is feasible at a large scale compared to the provision of electricity from traditional sources. This section reviews the current and predicted future technologies. As shown in figure 1, in the most common type of solar cell, crystalline silicon, there are two impure ‘doped’ layers of silicon, one more rich in electrons than the other; when excited by photons from the sun, the electrons jump through the barrier between the two layers, creating a ‘hole,’ which creates the impetus for electrons to flow through the circuit and re-establish equilibrium.

Figure 1: The functioning of a typical crystalline silicon photovoltaic cell (Mr. Sun Solar, 2006)

There are two main types of crystalline silicon: mono-crystalline and poly-crystalline. Between them they represent 93% of the solar market (solarbuzz, 2005). In the former case, silicon wafers are sliced from solid ingots, an expensive process that leads to waste. Efficiency (meaning the amount of sunlight striking the cell that converted to electricity) is highest in such cells however. Thus the story of PV technology development to date is largely one of finding cheaper manufacturing processes while maintaining useful efficiencies. The current main options include casting the silicon in a block (polycrystalline cells), and depositing thin layers of silicon on a solid substrate like glass in a vacuum chamber and etching the electrical connections (silicon thin film).


Figure 2: Mono-crystalline, polycrystalline and thin film solar cells

There is a range of other options, including different types of crystalline and thin film technologies, as well as novel approaches (NREL, 2006; Solar Century, 2006). Silicon:

• Ribbon and sheet cells, where the silicon is pulled out into long ribbons, or large sheets, reducing manufacturing costs.

• ‘Spheral’ cells, in which small balls of silicon are deposited on flexible aluminium

Thin films:

• Non-silicon thin film options include such materials as indium diselinide, cadmium sulfide, cadmium telluride, and indium phosphide.

• High efficiency thin films used elements in group III and IV of the periodic table, like gallium arsenide, and can reach 30% efficiency.

Adaptations:

• Cells that have the sunlight concentrated on them by lenses to increase efficiency

• Hybrid cells of both crystalline and amorphous silicon; • Multi-junction cells where different layers, including those containing non-

silicon materials, take advantage of different wavelengths of light, increasing efficiency.

New concepts

• Light-absorbing dye cells use a light sensitive fluid that may reduce manufacturing costs.

• Organic materials, e.g. using inexpensive plastics rather than silicon, where reaching useful efficiencies has been the challenge to overcome.

• High efficiency advanced concepts like quantum dots – where nanopartical materials are suspended in a conductive polymer matrix.

There is therefore a range of technological options among PV cells, and a substantial amount of research. The primary challenge is lowering cost, with the associated


factors being materials availability and costs; the potential for scale up of manufacturing; high enough efficiency to avoid needing too much surface area to be practical; durability, reliability, and stability (e.g. not having output degrade too significantly over time). Aside from the solar cells themselves, costs are also significantly influenced by the balance of systems (BoS) – the ancillary equipment such as the components needed for mounting, power storage, power conditioning and site-specific installation. As PV is scalable from a single cell to an array as large as desired, and can be either stand-alone (requiring storage) or grid-connected, the proportion of system price due to BoS is highly variable, but can be up to 50% of total costs. Technology development tends to be driven by progress in other fields – power conditioning equipment, for example, is not by any means dominated by the solar field (pvresources.com, 2006).

2.2 What are the benefits and drawbacks of PV? The first and foremost advantage of PV technology is its environmentally sound performance - it is one of the cleanest technologies available and has the potential to play a vital role for mitigating some of the most serious environmental problems (e.g. air pollution, climate change) PV technologies have also some technical advantages compared to other electricity generating technologies - they require low maintenance and can operate for long periods unattended; if needed, additional generating capacity can be readily added, which make them the a good choice for electricity generation in remote applications. Another advantage is the free accessibility of sunlight. Although its useful quantity at any one place depends heavily on latitude and weather, in global terms there is far more incident sunlight than needed to power the world1. Their poor economic performance is the key deficiency of photovoltaics. The relatively high upfront costs render PV energy generation the least attractive alternative (from economic point of view) among the on-grid electricity sources. On the other hand, when considering that the price of electricity in dry cell batteries is on the order of €50/kWh, a remote home owner might find PV cheap. Another major challenge is their power production fluctuation, due to the nature of the sunlight, nevertheless, sunlight is predictable within broader time ranges – fortunately, the sun always rises. Finally, a challenge for PV technology development to be overcome is the silicon shortage. Prices went from $9/kilo in 2000, to $25 in 2004 and $60 in 2005 (Planet Ark, 2005). Increases in silicon availability are expected in 2008, which should allow increases at production lines that are currently partially idle. But the shortage also explains enthusiasm for long-term options that use silicon sparingly, like concentrator

1 One estimate states that PV covering an area of 500 by 500 kilometres at 10% efficiency would equal

current primary energy output (Goodstein, 2004)


cells, reduce purity requirements, like spherical cells, or technologies that avoid it altogether (Lacoursiere, 2006).

1. PV markets and customers There are three primary applications for PV systems:

Commercial Products (watches, calculators, etc.) Off grid:

o telecommunications o off-grid domestic o off-grid industrial/commercial

On-grid: o small grid-connected (home) systems o central, large scale grid-connected

Figure 4 indicates the growth of the different categories. The main factor is the enormous growth of grid-connected solar homes, through such initiatives as the solar roof programmes in Japan and Germany.

Figure 3: The evolution of different market segments for PV, showing in particular the growth of on-grid systems, primarily small systems, or 'solar roofs’ (RWE Schott Solar, 2004) In terms of countries, Japan and Germany lead the world in annual installations by a large margin (Figure 4).


Figure 4: PV market growth 1998-2003, with Japan and Germany leading the pack (1998-2003 PV News and Strategies Unlimited)

The global annual growth rate of PV from 1992 to 2001 was 29%. In 2002, Japan, Germany and the United States accounted for 92% of new installations. Over the period 1998-2002, annual growth rates in Japan were 48%, 52% in Germany and 21% in the USA. The nature of the systems shifted since 1990 – then, they tended to be solely off-grid homes, telecommunications and commercial uses; now the market is driven by small on-grid building integrated PV. Despite the impressive growth rates, PV is still a tiny proportion of world electricity generation. Even in Germany, it accounts for a quarter of one percent of domestic electricity generation. The major question to be resolved is whether PV can move from a fast-growing but marginal energy source to a major player. The next sections will discuss the whether innovation will allow this to happen, and what is driving it.


3 INNOVATION IN THE CONTEXT OF PV

3.1 What are the indicators of innovation? Innovation is a concept that is difficult to quantify. Indicators include numbers of relevant patents, numbers of relevant scientists working in the field, company registrations, and others. In order to use a measure that is both simple and relevant to the desired outcome of market penetration, in this study innovation will be measured in terms of cost reductions. Cost variations indicate whether and when PV could be competitive with other energy technologies. The cost of a PV module is generally measured in euros or dollars-per-peak-watt ($/Wp), where ‘peak Watt’ is the amount of power a photovoltaic cell or module will produce at standard test conditions (normally insolation of 1,000 watts per square meter and 25 degrees Celsius). Cost reduction thus can be achieved either through a decrease in manufacturing cost, or though improvement in module efficiency, all other things being equal. This analysis thus will look at both cost and efficiency development, where:

• Costs is the costs per produced Wp • Efficiency is the portion of the incident solar radiation converted into

electricity

3.2 Current cost of PV systems The cost of photovoltaic systems usually includes two elements:

- module cost: cost of material - e.g. silicon wafer manufacture for single crystalline silicon module, cell fabrication and module fabrication. It is typically 40-60% of total cost

- Balance of Systems (BoS) cost: mainly battery (about half of BoS cost) and AC/DC converter (Ghosh, 1999). It is difficult to assess the typical BoS cost, as systems requirements can vary significantly for each application

Figure 5 shows PV system price trends in Austria, Germany, Japan, United States, Switzerland and the Netherlands. After a steep decrease in the 90s, PV systems prices tended to stabilise around 7 /Wp in 2001.


Figure 5: Development of PV system prices in 1990-2000 excl. VAT (IEA, 2002)

Although generally these are assumed to be the only components of PV costs, it should be taken into consideration that other elements influence the overall cost of a PV system, e.g. the cost for site preparation, laying foundations, system design and engineering, permitting, assembly and installation labour. Due to low standardisation, costs for PV systems vary widely. They depend on the system size, location, customer type, market, grid connection and technical specifications. High variability thus can be found across countries, for both on grid and off grid systems. According to a survey (Harmon, 2000) of PV installations in Western Europe, North America and Japan, in 1996 installed costs ranged from approximately $14/Wp to $27.60/Wp for ‘off-grid’ PV systems between 100-500 peak watts, and from 10/Wp to $15/Wp for 1-4 kWp systems. For on grid systems in the range of 1-4 kWp, the costs varied between $7/Wp and $15/Wp. Larger on-grid systems, between 10 and 50 kWp cost $7.50/Wp to $20/Wp, while systems larger than 50 Wp did not exceed $13.70/Wp (Bates, 1997). It should be highlighted that these costs were assessed in developed countries with established distribution chains and experienced PV system designers and installers. Worldwide, installation costs were higher, e.g. off-grid systems reach $30–$40/Wp. These data reveal that, while module costs are relatively uniform, total PV system costs may differ significantly, according to BoS requirements and the experience of the PV industry of a given region.


In addition, PV systems require periodic maintenance; although depending heavily on the nature of the system and its location, operation and maintenance costs may be approximately 2% of total hardware costs (Notton, 1998). Today PV is generally not price competitive compared to diesel power generation in off-grid applications where power demands are higher (though current high oil prices may change that assessment if sustained), and it is far more expensive than grid-connected electricity. Furthermore PV is also more expensive than other renewable technologies, such as wind turbines. Nevertheless, crystalline solar PV can still compete in smaller off-grid, developing country applications or in retail markets where power is generated at the point of use and is not subject to heavy transmission and distribution costs. Figure 6 shows crystalline solar PV costs as would apply to rural power generation in developing countries, assuming that solar PV will feed mostly into retail and off-grid markets.

Figure 6: Estimated cost of renewable and fossil fuel technologies in 2003 (Carbon Trust, 2003)

The main progresses in term of cost reductions have been achieved for building-integrated PV (BIPV) systems, whose average costs have been reduced by a factor of two in each of the last two decades. In recent years average installed costs have been about US$ 5-9 per Watt for building integrated PV (BIPV). Figure 7 shows the trend of BIPV costs compared to PV module production.


Figure 7: Annual world PV module production and building-integrated systems costs, 1983-2002 (IEA, 2004)

3.3 The future: price per area and performance per area; the differential importance of manufacturing costs and efficiency

Bringing PV costs down is a function of reducing manufacturing costs per area of cells, and/or increasing the efficiency of a given area of cells. Both aspects are the subject of development, but are generally not found in the same cells – that would be the Holy Grail. Between 1955 and today the efficiency of PV cells on the market has increased from 3 to 16 percent (see box 1). Nevertheless, the highest efficiency cells, namely silicon cells, are the most expensive on the market, while the more affordable thin film cells’ efficiency lies below 10 percent. More affordable materials and production outweighs increased efficiency in reducing the price per Watt. PV electricity is currently ‘cheaper’ if produced by the less efficient technologies. 1955: 3% efficiency cells 1957: Hoffman ELECTRONICS develops 8% efficiency cells 1959: 10% efficiency cells appear 1985: 8% efficiency modules are developed for the market Today: more than 16% efficiency modules are in the market, and over 30% in the lab. Box 1: Evolution of highest efficiency cells The level of efficiency, power and price of different technologies is plotted in the figure below.


Figure 8: Efficiency, price and power output for various technologies (RWE Schott Solar, 2004)

The least expensive technologies are new concepts such as nanocristalline dye cells with a 5 percent efficiency, on the bottom left of the graphic. Top efficiency (above 20 percent) is reached by non-silicon future technologies, but at higher price/W. High-efficiency high-price technologies could be preferred for space-limited areas, while wide areas (e.g. large skyscraper surface) can afford to use lower price/m2 technologies. Today this can be done most efficiently by amorphous silicon cells.

A recent study by EPIA (2004) suggests that in the long run integrated manufacturing of thin silicon wafers (100 µm or less) and subsequent cell and laminate making will likely be the most effective route of PV technology development (Table 1).

year 2000 2010 2020

Feedstock EUR/Kg 25 20 15 wafer µm 300 200 100 cell % 14-17 17-20 19-22 module long term stable, low cost/m2 technology

Table 1: EPIA road map for c-Si technology (EPIA, 2004)

According to other related studies (Hoffman et al., 2004), c-Si cells will most likely prevail until 2010, while first thin-film products and later new concepts (like dye and organic cell types, with either low materials cost or high efficiencies) will play a relevant role up to 2030. The goal for new technologies will be efficiency increase towards and beyond 20 and 30% for crystalline Si and III-V-compound multi band gap devices, large area thin film technologies aiming for beyond 10 m² area, low price per area building material, and the development of new concepts.


Figure 9: Technology road map (RWE Schott Solar, 2004)

3.4 Experience Curves One way to explain and describe cost reduction is to adopt the experience (learning) curve model. The model implies that learning acquired through cumulative production reduces costs. In the case of PV, learning is attributed to increases in module efficiencies, manufacturing experience and economies of scale. When examining the effect of learning on PV systems cost, though, it is useful to differentiate between PV modules and BoS. While PV modules are deeply related to PV experience, BoS are based mainly on mass-produced components, thus improvements are more the result of spillover knowledge from other sectors. The learning curves presented here therefore focus on PV technology alone. According to the learning curve theory, an increase by a fixed percentage of the cumulative production implies a percentage reduction in price. Figure 10 represents the learning curve for PV in the world market between 1976 and 2002


Cumulative PV production (MWp)

Figure 10: Experience curve for PV (Johnson, 2002; Dunay, 2003)

The so called progress ratio (PR) gives the change in price corresponding to a doubling of the production volume. Data from 1976 to 2002 reveals a progress ratio of 80%, meaning that the price is reduced to 0.8 of its previous level after doubling cumulative sales. Another way to express the change in price is given by the learning rate (LR), where:

LR = 100 — Progress Ratio

In this case the LR would be 20%, meaning that each doubling of sales reduced the price by 20%. The fact that the progress ratio is the same for any part of the experience curve implies that young technologies learn faster from market experience than old technologies with the same progress ratios (this happens because the x-axis scale is exponential). In the case of PV, market expansion from 1 to 2 MW reduced prices by 20% when the technology was first introduced, but at a later stage production had to grow faster to have the same price reduction, e.g. from 100 to 200 MW. In terms of actual cost, prior to commercialization, in 1968, laboratory-based PV modules cost approximately $90/Wp (Maycock/Wakefield, 1975). After 1976, when the commercial manufacture of solar cells started, crystalline silicon PV module prices dropped from $51/Wp to approximately $3.50/Wp in 1998 (Ayres et al., 1998; Thomas et al., 1999). It should also be taken into consideration that, although not strictly correlated to PV learning, BoS contributed to the decrease of the overall cost of PV systems. For instance cost reductions have been attained through greater system integration and a reduction in the number BoS parts. A strategic opportunity for further reducing BoS costs will be standardizing BoS to the greatest degree possible and efficiently packaging components so that on-site integration and installation in minimized (Harmon ,2000). Future price cuts would likely results from discrete technological innovation, e.g. the development of micro-inverters as a cost-effective replacement for traditional inverters (Ghosh, 1999).


According to a recent study by IIASA (Nemet, 2005) learning derived from experience is only one of several explanations of the change in the main factors affecting the manufacturing cost of PV, such as plant size, module efficiency and silicon cost. Its role indeed appears minor compared to that of R&D and knowledge spillovers from other industries rather than experience and learning from cumulative production. This weak relationship suggests cautious consideration of the conditions under which experience curves can be relied upon to predict technical change.

3.4.1 Expectations on future PV costs How far PV costs need to come down to be deployed on a large scale is a matter of debate. Several studies have been undertaken to assess the future trend of PV costs, in order to establish whether and when this technology would be cost efficient enough to take the place of conventional energy sources, and the order of investment required. An IEA study based on learning curves looked at how the cost of PV modules has to be brought down to the cost of the so-called ‘fossil fuel alternative’, estimated to be around 0.5 US$/Wp (Figure 11).

Figure 11: PV break-even point (IEA, 2000)


Figure 12: Historic and projected learning curve for PV (Sanden, 2004)

For moving down the experience curve, further learning efforts are needed. The resources required to improve learning in order to reach break even may be defined as the difference between actual price and break even price. These additional costs are referred to as learning investments, i.e. those investments needed to make the technology cost-efficient. Once the break even point is reached they will be recovered as the technology continues to improve. In Figure 12, costs are projected to possibly halve by 2012, and to meet the break-even cost compared to fossil fuel alternatives around 2021. The investment needed to achieve this is estimated at $14 billion per year until 2021, which is the equivalent of an OECD-wide tax of $0.001 per kWh on electricity (Sanden, 2004)2.

3.4.2 The nature of experience and learning Experience curves plotted from historical data and extrapolated into the future are appealing when they seem to match the data well, as they do in the PV case, but they are clearly simplifications, and raise questions as to what is actually happening to cause the reductions. Once one begins to look into the details, questions emerge about the approach altogether. Nemet (2005) notes that different curves drawn with different data yield vastly different conclusions. When two major data sources on historical PV costs are compared and extrapolated into the future, the estimated point at which PV costs reach $0.30/Wp differs by 28 years (Figure 13).

2 To put this in context, the cost of the Iraq war is estimated to reach $315 billion by September 2006

(www.costofwar.com) – a cost totally unanticipated just four years ago, and, some might argue, delivering far fewer benefits than a transition to a clean energy economy.


Figure 13: PV experience curves with two data sets (Nemet, 2005)

The paper argues that it is important to understand the dynamics behind the cost reductions. Accordingly it uses factor analysis to find that the most influential factors in PV cost reductions have had little to do with learning by doing as such, but rather with demand pull, R&D, and spillovers from other industries.

Table 2: Factors in PV cost reductions 1975-2001 (Nemet, 2005)

Nemet goes on to develop the model to predict future cost reductions, on the basis of assumptions about potential improvements in specific important factors. He then compares the results to experience curves with two different assumed learning rates (Figure 14). A 0.23 learning rate, which has been determined over the period 1975-2001would, would deliver $1.00/W modules in 2027 and $0.10/W in 2086. A more conservative learning rate, 0.10, projected using more recent trends, would delay $1.00/W modules from 2027 until 2076, and $0.10 would not be reached by 2100. Contrasted to these is the outcome of a model in which $1.00/W modules are achieved in 2050. This implies an industry growth rate of 11% for the next 45 years. At that point, 1.3 TW of PV would have been installed at a cost of $1.5 trillion, with PV plants manufacturing 1.9 GW of modules annually. Such a scale is considered feasible in a recent National Renewable Energy Laboratory study (Keshner and Arya 2004) showing that in this scenario, 48% of the cost reduction comes from efficiency improvements and 51% comes from scale.


Figure 14: Scenarios using cost model, experience curves and $1.00/W target price (Nemet, 2005)

3.4.3 Conclusions about learning Different models provide different estimates of PV cost evolution. The learning curve model proved to be a good system to estimate trends, but it may overlook other factors besides learning that influence price reductions. Nevertheless, learning curves models provides some interesting insights on PV cost evolution. Compared to other energy technologies, PV has higher relative cost but a steeper learning curve, as shown in Figure 15. This can imply that further investment in PV can lead this technology to improve faster than others.

Figure 15: Electric technologies in EU, 1980-1995 (IEA, 2000)

Future models will need to take into account other factors, such as R&D, knowledge spillovers, and market dynamics to provide a more realistic picture for future investments.


In addition the potential of technologies currently at an earlier stage, such as so-called third generation solar PV based on polymers and nanomaterials, should be recognised. These could potentially overcome today’s technologies and offer lower cost renewable power – creating a noticeable discontinuity in the learning curve. Their development paths though are much less certain than the other well know photovoltaic technologies, and it is difficult to establish when and if they would substitute existing systems, and what consequences they could have on renewable energy costs (The Carbon Trust, 2003).


4 POLICY SUPPORT FOR PV

4.1 The context Solar energy started as a means of powering satellites: early modules produced energy reliably, at exorbitant prices. The first oil crisis in 1973 brought the ambition for solar down to earth: it was the main driver for the launch of Japan’s renewables promotion programme, which started with the so called Sunshine project (Jaeger-Waldau, 2003); the early 70s energy crisis even led to installation of solar panels on the White House during the Carter Administration (famously removed by President Reagan immediately upon entering office).

Currently, climate change is the main driver of interest in solar energy, with security of the energy supply remaining an important second factor. Further, perhaps more than any other energy technology, PV is simply popular among the public for its promise of harnessing ‘free’ energy cleanly. It also appeals to policymakers for its technological cache. As US President George Bush (no fan of the Kyoto Protocol) summed up in a recent visit to a solar energy production facility3, ‘we've got great inventors and great entrepreneurs here in our own country, preparing for ways to enable the American people to get rid of our addiction to oil. And that will not only enhance our economic security, but enhance our national security, as well.’

4.2 European policy By increasing the share of energy generated from renewable resources the EU will reduce both its greenhouse gas emissions and its fuel import dependency. Recognizing the important role renewables in both goals, in 2001 the EU adopted the Directive on the promotion of electricity from renewable energy sources in the internal electricity market (COM 2001/77/EC). By the year 2010 12% of energy and 22% of the electrical energy in the Union should be generated from renewable sources.

The Directive leaves the choice as regards the design of their individual renewable energy portfolios to the Member States. Given the costly installation and the relatively low capacity of PV, this lack of differentiated treatment requirement between the different renewables might facilitate the promotion of better developed and more cost efficient one to the detriment of the PV.

The primary climate-related policy instrument with potential impacts on PV technology development in Europe is the EU Emissions Trading Scheme (EU ETS). This market-based mechanism requires carbon emitters to hold emissions allowances, and make reductions over time. This therefore should indirectly promote renewable energy sources as they do not have to surrender carbon allowances. Its positive effect, however, depends to a great extent on the proper functioning of the carbon market - the lower the CO2 price, the less the implied benefit for renewables (certainly it is too low to provide much of an incentive to PV) – further, if allowances are extended in excess of requirements they become a boon rather than a cost for emitters.

3 20 February 2006, at United Solar Ovonic, Auburn Hills, Michigan;

http://www.whitehouse.gov/news/releases/2006/02/20060220-2.html


In 2005 a new European initiative, aiming at bringing together all relevant stakeholders from science, industry and policy in the PV sector has been launched. The objective of the European Photovoltaic Technology Platform4 is to increase networking between the different actors to “contribute to a rapid development of a world-class cost competitive European PV for a sustainable electricity production”. The co-operation within this platform has been divided into four working groups, gathered around the following issues: (1) policy and instruments, (2) market deployment, (3) science, technology and applications and (4) developing countries.

The creation of such a forum at European level is a very important step for the PV technology to move downwards the learning curve. By boosting the interaction and skill-sharing among the stakeholders it contributes strongly to improvement of the efficiency of their work.

4.3 National policy instruments While European policy sets a framework and goals for renewable energy development, the various national policies reflect different approaches, and one might argue levels of commitment, to pushing renewable energy. Further, there are different approaches to specifying support for PV. Here we give and overview before selecting three countries to look at in more detail: Germany, the UK and Japan. At present, policy instruments designed to support PV dissemination are based mainly on state subsidies (whether directly from the state or via market actors through policy requirements, like feed-in tariffs) and fiscal mechanisms (figure 2).

4 http://www.eupvplatform.org/index.php?id=37

Subsidies

Output subsidies Input subsidies

Regulating the price (Feed-in tariffs)

Regulating the quantity (Quota models, Competitive tenders)

Fiscal Mechanisms

Carbon and energy taxation

Policy instruments

Capital subsidies


Figure 16: Categories of subsidy models (Schaller, 2005)

The feed-in tariffs model is an instrument which guarantees the producers of electricity from renewable sources a fixed price at which they will be able to feed this electricity in the grid. This fixed tariff leads to a price increase of the electricity which, due to the small share of the electricity from renewable sources in the grid, is however relatively low. The Quota model is an instrument which aims at achieving a certain quantity of electricity from renewable sources. It obliges power retailers to cover a share of their energy demand from renewables, for which they receive the so called “Tradable Green Certificates” (TGC). Similarly to the EU ETS, at the end of a given period each entity has to be in possession of the required amount of TGC (which can be acquired either by using renewable energy or by buying surplus certificates from other retailers). Competitive tendering is a method based on an auctioning of a certain amount of capacities for renewable energy. The entities with the best bids receive either an output subsidy (a fixed price, similar to the feed-in tariff) or a capital subsidy. Capital subsidy represents a state funding (via direct grant or soft loans) for private companies, public organisations or individuals of certain portion of the upfront costs for PV installation. Carbon and environmental taxation is a fiscal mechanism which aims at internalisation of environmental costs of carbon intensive energy generation (e.g. EU ETS), and respectively favourites the energy generated from renewable sources. The following table gives an overview of the application of the described policy instruments in Europe.

Table 3: Present (x) and current (h) supporting mechnisms in EU-15 (EEA, 2004)

4.4 What are the merits of the existing policy instruments? Policy measures that generate cost pressure are theorised to be best placed to promote technology innovation (Brauer/Kuehn, 2005). Under this assumption, the quota model and competitive tendering are best to serve this purpose. These models create a competition situation (the electricity retailers will cover their quotas by buying from


the most cost efficient renewable sources) which pushes the producers of renewable energy to innovate in order to safeguard their market position (Brauer/Kuehn, 2005) The arguments hold true only if all renewable technologies are at the same stage of development, or if a differentiation is made to reflect the different stages of development. Otherwise, these two policy instruments may undermine the chances for market deployment of emerging technologies, as they are beaten out by more advanced options. In other words, the quota model and competitive tendering may be beneficial for PV technology, if they take into consideration the early stage of development of this technology. Otherwise they will lose to sources like wind and biomass – which has happened in the UK’s undifferentiated renewables obligation system. Schaller (2005) asserts that not only the “punishment” (through cost pressure) but also the “reward” (the prospects of higher profits) may encourage innovation. Even though it is difficult to assess which of these incentives has the higher potential to spur innovation, Schaller argues that the feed-in tariff model entails two main advantages with this regard. On the one hand, it does not set a cap on the energy production from renewables (as opposed to the two other models), which does not only benefit the environment, but it also leads to accumulating economies of scale and learning experience as a result of increased production volume. On the other hand, the feed-in tariff model rewards those electricity generators that manage to produce more cost efficiently by guaranteeing higher profits. In order to initiate innovation behaviour, however, it is essential that the tariffs decline with the time (Schaller, 2005). As far as PV technology is concerned, the long term price that the feed-in tariffs model guarantees constitutes an investment incentive for the industry, which is very important in this stage of development of the technology. Yet, for the effective support of PV technology it is crucial that the tariff levels are designed so as to take into account the relatively high production costs of the technology.

4.5 How do the policy instruments affect innovation? Germany, Japan and the UK are instructive case studies of policy intervention. They apply different policy instruments to promote PV, and represent both leaders (Germany and Japan) and a laggard (the UK) in the PV market. In the following, the three countries’ policy instruments shall be reviewed and some preliminary conclusions as regards their effectiveness to create a self-sustained PV market are drawn.

4.5.1 Germany The following table gives an overview of the major policy instruments for promotion of PV in Germany.

Policy Operating principle Year of implementation 1.000 roofs Investment subsidy of 70% of

costs with upper cap 1991-1995

Electricity Feed-in Law (Budget 3.5 M EUR paid by final customer)

Feed-in tariffs (90% of the average price for end consumer)

1991-03.2000


Cost covering feed-in tariffs from utilities and local communities

Feed-in tariffs of up to 1.12 EUR/kWh fixed for 20 years

1996-1999

Green tariffs from utilities as voluntary participation for the customers

1) higher feed-in tariffs paid to realise new PV plants

1996-1999

Market stimulation programme

Invest. subsidies on schools, churches and congregations

1999-2001 (on schools still ongoing)

100.000 roofs (Subsidy of 695 M EUR)

Soft loan: 10 years duration, 2 years free of redemption

1999-2003

Renewable Energy Act (Budget 83 M EUR paid by final customer)

Feed-in tariff of €0.457 fixed for 20 years (5% decrease annually for later installation from 2002 on)

01.04.2000-ongoing

Promotion of research projects in the field of PV

Financial support for joint projects by research and industry entities

2004-ongoing

Table 4: Promotion programmes in Germany (Schaeffer et al., 2004; BMU, 2004)

As shown in the following diagram, the introduced policy measures have yielded increases in the production and application of PV technology in Germany. In 2004 Germany overtook the world leadership as regards the yearly installed PV capacity – 363 MWp as opposed to 272 MWp installed by the second one – Japan (BMU, 2005).

Figure 17: The timing of the major policy instruments in Germany (RWE Schott Solar, 2004) Furthermore, a drop in prices for PV systems in Germany of almost 40% has been observed since 1995. According to a 2003 report of BMU, however, the price decrease in that year reflects market dynamics (increased competition by foreign producers) rather than cost reductions resulting from technology innovation (BMU, 2003).

Table 5: National trends in system prices for a 2-3 kW PV systems (BMU, 2003)


Features of the German PV policy: it stimulates PV energy generation by guaranteeing the industry a long-term

price it stimulates R&D activities (increasing budget) it stimulates the market for PV systems

4.5.2 Japan The following table gives an overview of the major policy instruments for promotion of PV in Japan.

Policy Operating principle Year of implementation

Sunshine Project Promotion of research activities aiming at development of technologies from alternative energy

1974 - 1994

New Sunshine project Successor of the aforementioned project, integrating the Sunshine, the Moonlight (Energy-saving technology R & D) and the Global Environment Technology Projects aiming at acceleration the market penetration of the technologies

1993 -2000

Projects for New Energies (1) Seed identification – related to production technologies, industrialisation and commercialisation (up to 50% funding) (2) Advanced PV Generation - 100% sponsored development of pilot plants for new PV technologies

2001

Monitoring programme for residential PV systems

Aimed at stimulation of the PV market. 50% of PV installation costs were subsidised

1994-1996

Programme for the development of the infrastructure for the introduction of residual PV systems

Successor of the aforementioned programme with substantially increased funding facilities.

1997

PV Field Test Project for Industrial Use

Subsidy (50%) for private companies, local public organisations for installation of PV systems

1998

Subsidy programmes of local governments

Funding of up to 40% of the installation costs

Renewable portfolio standard (RPS) Legislation aiming at achieving a ratio of 3.2% for the renewable energy in the total energy supply till 2010. It requires each power retailer to set an annual sales target for six types of renewable energy (including PV)

1st April 2003

Table 6: Promotion programmes in Japan (Jaeger-Waldau, 2003; Takigawa, 2006; Ikki/Tanaka, 2004)


Table 7: Cumulative installed PV capacity (note: in kW, not MW) in four market niches (Ikki/Tanaka, 2004)

Table 8: System prices trends in Japan (Ikki/Tanaka, 2004)

Features of the Japanese PV policy:

it promotes R&D activities (increasing budget) it stimulates the market for PV systems The goal for the market for renewables is more limited - the RPS aims at

raising the proportion of energy from renewables in the total power supply to “only” 3.2 % by 2010 (much less than Europe’s 12%) and for electricity generation to 12.5% (compared to 22% in the EU).

the RPS allows discrimination between technologies, but doesn’t require it: suppliers can choose

4.5.3 UK

The following table gives an overview of the major policy instruments for promotion of PV in the UK.

Policy Operating principle Year of

implementation Major Photovoltaics Demonstration Programme (PVMDP)

Grants between 40% and 50% are paid for installation of solar electricity panels. These are available to householders, business or social housing groups.

2002-March 2006

Low Carbon Buildings Programme This programme supersedes the aforementioned one, with the support of PV installations being a substantial part of it.

April 2006

Renewables Obligation The Obligation requires suppliers to source an 2002


annually increasing percentage (5.5% for 2005/06) of their sales from renewables. For each megawatt hour of renewable energy generated, a tradable certificate called a Renewables Obligation Certificate (ROC) is issued.

Financial incentives 1) Climate change levy exemption for PV

Table 9: Promotion programmes in UK (Energy Saving Trust, 2006; DTI, 2005)

1996 1997 1998 1999 2000 2001 2002 2003 2004 PV generation

(GWh) - - - 1 1 2 3 3 4 Cumulative installed PV

capacity (MWe) 0.4 0.6 0.7 1.1 1.9 2.7 4.1 6.0 8.2

Table 10: PV generation and cumulative installed capacity in the UK (DTI, 2005)

A large proportion of the present PV market is made up of off-grid applications (e.g. marine buoys and navigation aids, to trickle charge batteries for agricultural applications, to provide power for lighting systems and telephone boxes) (British Photovoltaic Association, 2000). Features of the UK PV policy:

no strong commitment to promote PV technology is visible the Renewables Obligation policy does not differentiate between the

technologies at different stages of development According to the Carbon Trust report, “it [UK] has arguably “missed the boat” in conventional solar PV”. It identifies the chances for the UK to develop a competitive position as regards PV technology in supporting the so called “3rd generation PV technology”, such as solar polymers for buildings. The report recommends the promotion of research and international cooperation programmes in this field (The Carbon Trust, 2003).

4.5.4 Comparing the innovation outcomes of national policy instruments Ultimately, the goal of policy is to create a self-sustaining PV market. Several conditions are needed; Jacobsson and Laubner (2006) have outlined the following key features of the early stage of such processes:

institutional changes

market formation

formation of technology-specific advocacy coalitions

entry of firms and other organisations


The process of achieving a self-sustained market commences with changing the existing institutional set-up. The alterations include adjustments in the regulatory framework (e.g. market regulations, tax policies), but go also as far as implementation of appropriate scientific and educational policies. The institutional changes aim to facilitate the knowledge accumulation and market formation.

Once an early market has been created, it attracts new entrants and variety of other interests groups, the growing number of which provides for legitimacy of the new market and increases the influence of the stakeholders in the further institutional shape (Jacobsson/Laubner, 2006). The existence of a self-sustained, competitive PV market is a necessary condition for spurring innovation activities in this sector.

In comparing Germany, the UK and Japan in the above context, several lessons emerge. The feed-in tariff’s main advantage is that it guarantees sustained above-market payments for the still costly PV technologies – the guaranteed feed-in tariffs for the electricity from PV are considerably higher than for the other technologies (50.62 cents/kWh for electricity from PV as opposed to 8.7 cents/kWh for wind energy). These tariffs, however, differentiate according to the year of the installation – the later a PV system has been installed the lower the guaranteed tariff. Thus, the German model combines both measures for encouraging the PV market formation (by creating long-term investment incentives) and PV technology innovation (by reducing the tariffs and creating price pressure).

The Japanese quota approach allows suppliers to set differentiated targets in the RPS, but they can divide the percentage as they want, meaning they can choose the cheapest source, effectively making it similar to the UK approach. While this is the main policy now, much of Japan’s PV development to date has been driven by specific large programmes like the solar roofs initiative – it is therefore expected that the new RPS approach will not lead to as much installation. Developments in the PV market in Germany seems to support the proponents of the German approach – the installed PV capacity in Germany for 2004 was almost twice as much as that in Japan (BMU, 2005). Even though the turnover of Japanese PV producers has grown by 60 % in 2004, it has been realised to greater extent abroad (not least in Germany) (Takigawa, 2006). These figures let us conclude that the German PV policy in the last couple of years has been more successful in promoting market development, while the Japanese have managed to stimulate PV manufacturing even more than the PV market (Takigawa, 2006). At European level, a review by the European Commission of renewable energy support schemes around Europe, released in December of 2005, evaluated current renewable energy policy and support schemes in light of a country’s potential by the year 2020. It found that Germany had the second-highest effectiveness, while the UK policy generally had quite low effectiveness – for example, less than 1per cent of the amount of onshore wind that could feasibly be installed by 2020 is being added year on year – in other words, the potential total will be badly missed. For biomass electricity, the effectiveness is just over 1per cent and for photovoltaic energy it barely registers above zero. What is particularly interesting is that the UK has chosen renewables obligations and exemptions from the climate change levy that, when converted into monetary terms,


are on the order of the same level support as other countries where support is deemed more effective (as noted in Figure 18 and Figure 19), where the feed-in tariffs in Germany, Luxembourg and Austria yield more effective policies).

Figure 18: Generation costs of PV (blue bars) compared to national support levels in the EU 15 (red bars) (European Commission, 2005)

Figure 19: Effectiveness level of policies to promote PV in the EU15 - Germany and Luxembourg use feed in tariffs to great effect (European Commission, 2005)


These results highlight the importance of choosing a proper instrument to achieve the best results. The Commission’s review finds that feed-in tariffs are very effective in driving take up of renewable energy by comparison with quotas.

4.6 The link between market penetration and innovation As noted in the experience curve discussion above, cost reductions are held to be a function of cumulative installations. Thus anything that increases installations effectively, like Germany’s feed in tariffs, are presumed to bring down costs effectively. However, as also noted, there are forces at work behind these numbers that actually explain the mechanisms for cost reduction. These include:

• Step changes in the scale of manufacturing as PV shifts from supplying restricted niches like satellites to broader ones like telecommunications, to even larger ones like grid-connected homes;

• R&D on the essentials of PV technology as such, including efficiency and materials use

• Spillovers from other technologies like silicon chips and power conditioning equipment have improved PV prices;

Although often thought of as the driver for innovation in an emerging technology, R&D and materials shifts have accounted for less than half of the price drop in PV over the past 30 years (Nemet, 2005). Further, this kind of work takes place overwhelmingly in non-commercial laboratories with links to commercialisation that are not always direct (Nemet, 2005). Most public support has aimed at generating market pull, through such programmes as the feed-in tariff. PV is treated as just another commercial generating technology rather than a research project, albeit one needing significant financial support. Expansion of PV is to a certain degree linked to lowering marketing and installation costs, but with the latter being largely dependent on wide-scale market diffusion – this is a Catch-22 for a young technology, which market support helps overcome (Sanden, 2005). For the long-term, innovation is needed throughout the PV product chain: cheaper materials, cheaper manufacturing, useful efficiencies, reliable, durable, effective in various applications, with a marketing, installation and maintenance force supporting it. At the moment, no one technology has it all: cheaper manufacturing is paired with low efficiencies and vice versa. It may well be that there is no one solution even in the long term: the applicable technology will depend on the demands of the customer. In summary, several insights and lessons can be drawn regarding PV innovation:

• There are several generations of PV technologies at different stages of development, and which are likely to be appropriate to different niches. It is difficult to speak of one PV technology. As such, discontinuities may be expected in the future; the learning curve we see now may well flatten for silicon, but jump down for new materials, for example.

• Cost reductions and innovations come from many parts of the value chain. The benefit of PV efficiency gains for a given technology are only one factor: cost-effective manufacturing and materials use is vital, as are a robust actors engaged in marketing, installation, operation and maintenance, as well as BoS cost improvements.


• Cost reductions are not due just to R&D into PV itself – there are important spillovers from other technologies. This means that significant attention should be paid to harnessing those spillovers through research networks.

• Barriers to development of the PV market come from different areas. Some are technical, e.g. inherent efficiency limitations, others are locational (e.g. insolation levels), others are market-contextual (prices of silicon affected by other demand), others are human capacity (installation capacity; learning by doing), others are related to the effectiveness of policies and the context in which they operate (e.g. non-differentiation of RES support in UK de facto excludes PV)

• In some cases competition is good – PV to PV competition within a technology-banded RPS can inspire cost savings – in other cases competition is bad – PV exposed to competition from cheaper technologies means it is simply not taken up. On has to decide what ones wants – having any renewable energy, or developing PV.


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