1. Parth Vaishnav Nathaniel Horner Inês Azevedo
Where do the benefits of distributed solar PV exceed the costs? 34th USAEE / IAEE North American Conference October 25, 2016
Parth Vaishnav
Nathaniel Horner
Inês Azevedo
Make the title a question

2. Motivation Are subsidies for rooftop PV paying for themselves?
Will currently installed PV systems pay for themselves?
How are system capacity and subsidies distributed?
Resources / costs different

3. Evolution of benefits over time
AP2
EASIUR
CEMS
NREL
TMY3 data
1kW
Marginal benefits based on Siler-Evans et al.
Electricity generated
x (
Environmental benefits )

4. Evolution of benefits over time - EASIUR

5. Evolution of benefits over time – AP2

6. x ( + ) Benefits AP2 EASIUR CEMS NREL TMY3 data
LBNL dataset of installed systems (560k systems)
Marginal benefits based on Siler-Evans et al.
Summed for each year of a system’s 20-year life
Electricity generated
x (
Electricity price +
Environmental benefits )
Consumption displaced
Electricity sold back to grid
LMP
Retail price
Commercial and Residential Hourly Load Data (NREL)

7. x x x x x Costs Total installed price Deflator Rebate Customer cost
System Size x
Current cost per kW by state and by customer type x
Deflator
System Size x
Current cost per kW equal to SunShot target x
Deflator

8. System cost for customers
Based on mixed electricity prices and historical system costs – EASIUR System costs will exceed benefits by $4 billion. Air quality and CO2 benefits exceed rebates
$1.3 billion
$2 billion
$3.1 billion
Air damage reduction
CO2 damage reduction
Electricity sales
Customer rebate
System cost for customers

9. System cost for customers
Based on retail electricity prices and historical system costs – EASIUR Benefits would exceed costs by $3.4 billion
$2.8 billion
Air damage reduction
CO2 damage reduction
Electricity sales
Customer rebate
System cost for customers

10. $1.2 billion System cost Air damage reduction CO2 damage reduction
Based on mixed electricity prices and current system costs – EASIUR At current system costs, costs would exceed benefits by $2.6 billion
$1.2 billion
Air damage reduction
CO2 damage reduction
Electricity sales
System cost

11. Based on mixed electricity prices and current system costs – EASIUR At current prices, installed base would have cost $1b less
Barbose, G., Darghouth, N., Tracking the Sun VIII: The Installed Price of Residential and Non-Residential Photovoltaic Systems in the United States. Lawrence Berkley National Lab.
Don’t show line for EIA installed capacity

12. If the current installed base had achieved SunShot targets, the net benefit would be $20b
Air damage reduction
$11 billion
CO2 damage reduction
Electricity sales
What is the break-even module price
System cost

13. More capacity has consistently been installed in richer counties
2015
2011

14. More rebates have gone to richer counties, but volume of rebates is falling
2011
2014

15. Rebates go to richer counties
Rebates go to richer counties. Distribution of rebates is getting closer to that of population
All systems
Distribution of county incomes weighted by population
Distribution of county incomes weighted by rebates in 2013
Distribution of county incomes weighted by rebates in 2000
County median income ($ per year)

16. Rebates go to richer counties
Rebates go to richer counties. Distribution of rebates is getting closer to that of population
Commercial
Installations
Distribution of county incomes weighted by population
Distribution of county incomes weighted by rebates in 2013
Distribution of county incomes weighted by rebates in 2013
County median income ($ per year)

17. Conclusions Systems are cheaper now
But the grid is cleaner also
System costs exceed benefits, even after accounting for CO2, air quality improvements
Not true in many states if all generation valued at the retail rate
Not true if the SunShot target is met
Air quality and greenhouse gas benefits exceed rebates
Value of electricity produced does not exceed the cost to customer of installation
Systems and rebates have flowed to richer counties
Distribution of rebates has started to match distribution of population more closely

18. Acknowledgement
This work was supported by the center for Climate and Energy Decision Making (SES ), through a cooperative agreement between the National Science Foundation and Carnegie Mellon University

19. Back-up

20. Extends two papers that have been presented at CEIC in the past
UPDATED
I’ll start by a quick introduction to the topic, and my motivation for researching it
We’ll then dive into the actual analysis by discussing two technological interventions to cut emissions from the transport sector: one in aviation and one in shipping.
I’ll spend very little time on the first of these: the analysis has been presented several times in forums in CMU and outside, and has been published
I’ll also talk about a policy intervention – the International Civil Aviation Organization’s market-based mechanism to cap emissions from international aviation aviation at 2020 levels
The final piece is the second technological intervention; a cost-benefit analysis of shore power: the practice of grid using electricity to supply vessels when they are in port.
I’ll conclude by discussing some of the broad lessons we can draw from these studies
Hagerman, S., Jaramillo, P., Morgan, M.G., Is rooftop solar PV at socket parity without subsidies? Energy Policy 89, 84–94. doi: /j.enpol
Siler-Evans, K., Azevedo, I.L., Morgan, M.G., Apt, J., Regional variations in the health, environmental, and climate benefits of wind and solar generation. PNAS 110, 11768– doi: /pnas

21. System cost for customers
Based on mixed electricity prices and historical system costs – EASIUR Same conclusions as AP2 about benefits, rebates. AP2 and EASIUR produce similar results
$1.3 billion
$6 billion
Air damage reduction
$2.6 billion
CO2 damage reduction
Electricity sales
Customer rebate
System cost for customers

22. Benefits are ~3.2cents/kWh on average; but there is significant variation between states
Total installed capacity
Air quality benefits
CO2 reduction benefits
Electricity sales
CO2 and air quality benefit per kWh
Δprice to equate system price with electricity sales
Δprice to equate system price with total benefits
Carbon price to equate system price with total benefits
(MW)
($ million)
($ per kWh)
($ per tCO2) CA
3000
700
2000
9000
0.022
0.06
0.04
100 MA
1000
400
0.032
0.05
0.02 60 AZ
600
0.023
0.03 70 NY
500
300
0.059
0.07 30 NJ
200
0.080
0.15
0.10 NV
0.027 40 CT
0.035
0.09 PA 80
0.073
0.13 TX
0.028 MD 50
0.069
0.08
0.01 20 NH FL
0.033 NM 10 90 DE
0.070 WI OR 4
0.040 UT 5 2 MN 3
0.075
0.23
0.17 RI 1 AR
0.5
0.036