Cost and Finance in Off-Grid Energy Access

Transcription

1 Cost and Finance in Off-Grid Energy Access Berkeley Rural Energy Group Daniel Soto Sonoma State University 21 March 2014

2 Introduction How do we accelerate the pace of energy access, particularly the adoption of watt-scale devices How do we ensure that these devices are accessible to all income levels? Product cost and financing both important

3 Parallels between US and off-grid

4 Manhattan blackout People exhibit identical behavior in disaster blackouts and off-grid environments

5 Top investors target the residential solar leasing model US Third party financing To address the growing residential opportunity, many of the world s leading PV manufacturers have opened new business units and launched financing and hardware product Growth solutions infor financing the market. options More importantly, led to an the channel increase usedrooftop serve the solar residential market has shifted quickly in the past three years. In H1 2009, third party ownership Financing with leases is key represented to off-grid less thanenergy 20% of the access California residential PV installation market, while in H solar leasing claimed >70% market share % Calfornia Solar Initiative Residential Installations 80% 60% 40% 20% 0% H H H H H H H H H H H Third Party Other 2

6 Outline Millennium Villages microgrids Pilot project Data gathered Lessons learned Future Work Affordability Negative recurring costs for consumers

7 Millennium Villages pay-as-you-go The primary objectives were to Demonstrate system for micropayments for electricity Remove upfront consumer investment Demonstrate technical feasibility Demonstrate customer acceptance

8 Typical sites

9 Millennium Villages Microgrid

10 Millennium Villages Microgrid

11 Millennium Villages Microgrid

12 Millennium Villages Microgrid

13 Customer education

14 Data Collected Per customer power and energy consumption on 3 second intervals stored locally Hourly data sent via cellphone to a server Customer transactions and credit balances recorded Allows for observation of account balance and payment regularity

15 Customer payment behavior Accurate reporting on the financial behavior of customers allows for an accurate calculation of risk and return.

16 Time with positive balance 70% of consumers maintained a positive balance over 90% of the time

17 Time with positive balance :00: :00: Fraction of Customers Percentage of Time With Credit Available

18 Positive balance and average expenditure Many customers with modest expenditures displayed consistent payment behavior. Soto et.al. ICTD 2012

19 Technical outcomes What technical improvements are suggested by these observations? Low cost metering solutions Battery, inverter, generator efficiency Reliability

20 Low-cost metering system UCB developed a low-cost metering system for microgrids Rosa, Madduri, IEEE GHTC 2012 System commercialized by a microgrid startup company

21 Inverter and generator efficiency Inverters and generators must be large enough to safely meet the highest demand Operating below the rated load results in lower efficiency What is the financial penalty for lower efficiency?

22 Load duration curves Lighting Lighting and Freezer 300 Average Hourly Power Fraction of Availability

23 Modeling of improvements Clear sky insolation model Semi-ideal inverter model Choose smallest battery and panel to meet demand energy balance

24 Cost penalty for inverter performance Cost (USD/kWh) Typical Flat 0 Day Night Constant Ligh:ng Freezer Soto, Modi, IEEE GHTC 2012

25 Battery comparisons Using same model, what is the dependence of system cost on the battery technology Lead acid batteries Inexpensive 1000 cycles of life 80% round trip energy efficiency Lithium iron phosphate Expensive cycles of life 92% round trip energy efficiency

26 System cost by battery technology

27 Trade off between cost and reliability Demanding high reliability as a design point can increase cost Goal is to enable microgrid designers consider reliability in the design process

28 Cost and energy shortfall probability (ESP) Lee, Soto, Modi, In Press, Renewable Energy

29 Future Work Affordability of energy access Financing of energy access

30 Negative recurring cost Payback is less important than a reduction in expenditures for many consumers If saving is difficult, little ability to pay above existing expenditures Pico-power product is an investment that generates returns in the form of avoided costs

31 Payback periods Device Initial Cost Monthly Revenue Months Payback Solar Lantern $20 $ Battery for $150 $ phone charging Battery selling $150 $ electricity

32 Returns and available financing Equivalent rate of return small lantern battery in a box retail electricity Life of term (months) Microfinance usually shorter than 12 months and above 35%

33 What are the drivers of finance rate and payback period? Perceived risk Investor demand Alternative investments Transaction costs Are there conflicting requirements for donors and recipients for initial cost and sustainability?

34 Impact on practitioners How do academics communicate with practitioners?

35 Thank you Daniel Soto