Techno Economic Assessment of Low Capacity CSP Systems in UAE conditions

Transcription

1 Techno Economic Assessment of Low Capacity CSP Systems in UAE conditions Arivenda Nagara, Sujata Dahal, Manoj Kumar Pokhrel Presentation for Grand Renewable Energy Conference 29th July, 2014, Tokyo, Japan 1

2 Presentation Outline Introduction System Definition System Modelling and Simulation Economic Analysis Conclusions 2

3 Introduction Arguments Leading to Research High potential solar radiation Increasing energy demand in Ras Al Khaimah (RAK) UAE s dependency in oil and gas Need for small and distributable power plants Ongoing research on linear Fresnel mirrors and its structure 3

4 Introduction Research Objectives Design a low capacity (160 kwe 600 kwe) CSP system with linear Fresnel mirrors considering RAK,UAE climate Investigate the economic viability of the designed CSP system 4

5 Introduction Linear Fresnel CSP System: How it works? Flat Mirrors in parallel rows Solar energy reflects back to receiver Steam produces on the receiver Steam turbine-generator for electricity production Other industrial thermal application 5

6 System Modelling and Simulation System Definition Solar Collector field system Thermal Storage system Power Block System 6

7 System Modelling and Simulation Design Input Parameters and Scenarios Solar Collector: Nova 1 LFC Turbine: Manufacturers A (153 kwe), B (300kWe), C (350 kwe), B (600 kwe) Scenarios 1, 2 and 3 turbines from A in parallel with and without storage Single turbine from B (300 and 600 kwe) Single turbine from C (350 kwe) 7

8 System Modelling and Simulation CSP System with Single Screw Turbine EBSILON : Discrete thermodynamics and energy balance simulation software for power generation systems 8

9 System Modelling and Simulation Comparision of Single with multiple Parallel Screw Turbine Thermal storage increases capacity factor of the plant, but sacrificing total cycle efficiency Increasing electric output increases total efficiency Energy dumped in condenser is very high and increasing with increasing electric output 9

10 System Modelling and Simulation Different turbines considered for comparision Turbine from manufacturers A, B and C: Input Parameters Parameters Turbine A Turbine B 300 kwe Turbine C Turbine B 600 kwe Turbine Type Screw Impulse Axial Axial Capacity 160 kwe 300 kwe 350 kwe 600 kwe Inlet Pressure 7.5 bar 40 bar 40 bar 40 bar Inlet Temperature 173 C 400 C 400 C 400 C Outlet Pressure 1 bar 1 bar 0.3 bar 0.1 bar Outlet Temperature 100 C 165 C 152 C 46 C Adiabatic Efficiency 60% 53% 41% 60% 10

11 System Modelling and Simulation Performance Comparision of Turbine A, B and C Systems using turbine B have better efficiency, require smaller collector fields Systems that have higher operating pressure and temperature benefit from lower water latent heat, require less energy to convert water to steam and increase total plant efficiency Systems that have higher operation pressure and temperature require much smaller solar field, even smaller area for higher output capacity System with turbine C gives lesser ratio than system with turbine B due to lower turbine efficiency 11

12 Economical Analysis LEC comparsion of design with different scnarios Parameters Value Remark Economic lifetime (years) LEC ( /kwhe) no incentives 99% availability LEC ( /kwhe) free loan incentive LEC ( /kwhe) free loan and subsidy incentives 99% availability 99% availability Incentives policy Spain for comparision: Easy loan up to 1.5 M with amortization period of 10 years Subsidy up to 37% of investment cost for 20 kw solar thermal power plant Feed-in tariff of 0.32 /kwh 0.34 /kwh * ! # * ! # * ! # *2 parallel turbine A with thermal storage;! 2 parallel turbine A without thermal storage; # Turbine C without thermal storage Note: Exchange rate on October 20th, AED = 0.2 EU = 1.4 USD Electricity prices for comparison: UAE: 0.04 /kwh /kwh (0.2 AED/kWh 0.4 AED/kWh) Spain: 0.18 /kwh 0.2 /kwh (0.9 AED/kWh - 1 AED/kWh) USA: 0.01 /kwh 0.18 /kwh (0.05 AED/kWh 0.09 AED/kWh) 12

13 Economical Analysis LEC comparision with diffeent plants Parameters Value Economic lifetime (years) LEC ( /kwhe) Two Parallel Turbine A (306 kw) 0.5 LEC ( /kwhe) Turbine C (350 kw) 0.34 LEC ( /kwhe) 50 MW Indirect Parabolic Trough CSP Plant ECOStar LEC ( /kwhe) 50 MW DSG Parabolic Trough CSP Plant ECOStar LEC ( /kwhe) 100 MW Indirect Parabolic Trough CSP Plant Sargent & Lundy LEC ( /kwhe) Residential Scale PV Thin Film Lazard LEC ( /kwhe) Residential Scale PV Crystalline Lazard Note: LCE cost on table is without incentives Standalone CSP plants cannot compete with PV technology on small scale Hybridization and polygeneration can be solution for small scale CSP systems Up scaling CSP plant capacity can bring LEC down, as electricity production is catching up with investment cost 13

14 Conclusion Conclusion Standalone system designed with turbine A is not efficient. The turbine converts very small heat to electricity compared to available heat in steam Heat dumped in condenser is very high. This potential heat can be used for second cycle such as; heat supply, absorption cooling or water desalination Parallel turbines arrangement increases total system efficiency, but with the cost of significantly increasing solar field area, and does not necessarily mean economically sound 14

15 Conclusion Conclusions (cont.) Increasing operating pressure and temperature gives better efficiency, smaller solar field area Standalone low scale CSP systems cannot compete with PV on electricity cost. Especially in UAE where electricity price is very cheap and is determined by low oil and gas prices Hybridization and polygeneration is a way to increase capacity factor and system efficiency as well as to utilize the potential energy dumped on condenser UAE does not have incentives mechanism for renewable energy. To compete with conventional power plants or PV, CSP s only way is to up scale electricity production, where electricity production can catch up with investment cost 15

16 Thank you Questions? 16