a novel design of sofc combined cooling, heat and power ... · total energy consumption. industry....

A novel design of SOFC combined cooling, heat and power (CCHP)

residential system in the UK

Xinjie Yuan

• Professor Richard Bucknall

Department’s Director of Research

• Dr Yuanchang Liu

Outline

1. Introduction

2. Literature review

3. Simulations & Results

4. Discussions & Future work

1. Introduction - Background

• Space and water heating

• Electric vehicles newly registered

• Charging & New peak periods

Total energy consumption

Industry Domestic Transportation Service

Natural gas Electricity

Heat, cooling and power demand

SOFC combined cooling, heat and power (CCHP) residential system in the UK

Supply side

• Regulations for new dwellings

• Insulated homes

• Alternative systems

• Doubled prices

• Rising peak temperatures

Fuel cell

• Energy conversion

• Lower heat to power ratio

• Thermal insulation

• High temperature fuel cell

1. Introduction

• Main research question:

• SOFC-based CCHP systems

• Historic demand data

• Tri-influence (Efficiency, Environmental and Economic impacts)

• Sizing values (Number of fuel cells, heat exchanger and absorption chiller)

• Objective weighting coefficients

2. Literature review

• Part of the review table

2. Literature review

• Example

2. Literature review• Distribution of fuel cells and cooling devices

2. Literature review

1. System modelling (Electrical & Thermal model)

2. Fuel inlet (Natural gas or Hydrogen)

3. Cooling: Freezer/Refrigerator (Heat-driven or Power demand)

4. Sizing methods (Subjective or Objective)

3. Simulations & Results

3. Simulations & Results

Single cell system modelling

Electrical only system

SOFC CCHP system

3. Simulations & Results

3. Simulations & Results• Electrochemical reaction modelling (Simulink)

3. Simulations & Results

• Three main over-voltages

3. Simulations & Results

• At various temperatures

3. Simulations & Results

Singhal, S. C. (1996) ‘Advances in Tubular Solid Oxide Fuel Cell Technology’, 1996 Fuel Cell Seminar, 135, pp. 28–31.Carl, M. J. (2008) ‘SOFC Modeling for the Simulation of Residential Cogeneration Systems‘.

• Double reference validations

3. Simulations & Results

• Cell voltage and power output

3. Simulations & Results

• Validation for specific heat capacity and equilibrium constant

1) Heat capacity from: Spiegel, C. (2008) ‘Fuel Cell Thermodynamics’, PEM fuel cell modeling and simulation using Matlab /. Burlington, Mass. ,pp. 15–48. doi: 10.1016/B978-012374259-9.50003-3.2) Equilibrium constant from: Callaghan, C. (2006) ‘Kinetics and Catalysis of the Water-Gas-Shift Reaction’.

3. Simulations & Results

• State-points main properties

3. Simulations & Results

Single cell system modelling

Electrical only system

SOFC CCHP system

3. Simulations & Results

1.Grey relationship analysis

2.Entropy-weighting approach

3. Simulations & Results• Evaluation of number of cells

3. Simulations & Results

Single cell system modelling

Electrical only system

SOFC CCHP system

3. Simulations & Results

3. Simulations & Results• Flow chart of the evaluation of SOFC CCHP system

3. Simulations & Results

3. Simulations & Results

HX 1: Air preheating

HX 2 & Abc 1: Freezer

HX 3: Domestic hot water

HX 4 : Space heating

Priority value

• Evaluation of SOFC CCHP system on the coldest day

3. Simulations & Results• Evaluation of SOFC CCHP system on the hottest day

HX 5: Space cooling

Abc 1: Space cooling

Priority value

3. Simulations & Results

3. Simulations & Results

• SOFC CCHP system: 91.78% on the coldest day

• SOFC CCHP system: 88.16% on the hottest day

3. Simulations & Results• Comparative analysis 1

- Separated production (SP) system – 20% H2NG-SOFC CCHP system

3. Simulations & Results• Comparative analysis 1

- Separated production (SP) system – 20% H2NG-SOFC CCHP system

(Winter) SP 20% H2NG-SOFC CCHP

Efficiency 79% 91.78%

Investment cost (￡) 1248.17 3059.50

Energy cost (pence) 265.72 68.83

Emission (mg/s) 9.15 3.71

(Summer) SP 20% H2NG-SOFC CCHP

Efficiency 47% 88.16%

Investment cost (￡) 1248.17 3059.50

Energy cost (pence) 101.22 26.55

Emission (mg/s) 4.62 2.07

3. Simulations & Results• Comparative analysis 2

- NG-SOFC CCHP system – 20% H2NG-SOFC CCHP system

(Winter) NG-SOFC CCHP 20% H2NG-SOFC CCHP

Efficiency 90.96% 91.78%

Investment cost (￡) 3059.50 3059.50

Energy cost (pence) 73.98 68.83

Emission (mg/s) 3.99 3.71

(Summer) NG-SOFC CCHP 20% H2NG-SOFC CCHP

Efficiency 87.71% 88.16%

Investment cost (￡) 3059.50 3059.50

Energy cost (pence) 28.97 26.55

Emission (mg/s) 2.26 2.07

4. Discussions & Future work

1. Fuel inlet

2. Different occupancy profiles

3.Multiple households

4. Energy storage system

5. Power control & Power quality control

Review of presentation

1. Literature review

2. Single cell & CCHP system modelling

3. Number of cells & sizing values

4. Entropy weighting approach & Grey relationship analysis

Thank you !

Q & A