This document discusses California's plan to meet its renewable energy and zero net energy building targets through significantly expanding distributed photovoltaic (PV) systems, with a focus on rooftop solar. It estimates California will need over 15,000 MW of new rooftop residential and commercial PV by 2020 to achieve these goals. It also outlines the economic and environmental advantages of distributed PV compared to large remote solar projects requiring new transmission infrastructure. Key challenges remain in fully aligning the utilities' business model with this distributed energy future.
California's distributed PV potential to meet 2020 net zero energy targets
1. California and distributed PV
GW Solar Institute Third Annual Symposium
Bill Powers, P.E., Powers Engineering
April 26, 2011
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2. John Geesman, California Energy Commissioner, 2007
source: California Energy Circuit, State Sees DG Providing 25% Peak Power, May 11, 2007.
“There’s an ongoing schizophrenia in state policy
between what we say we want to do and what
we actually allow to happen.”
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3. What is California’s plan? Energy Action Plan
Energy Action Plan Loading Order:
Energy efficiency & demand response
(net zero energy buildings – EE/rooftop PV)
Renewable energy
Combined Heat & Power - CHP
Conventional gas-fired generation
Transmission as needed
Challenges – 1) inadequate regulatory oversight,
2) energy efficiency and distributed generation
run counter to conventional utility business model
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4. How much rooftop PV does California need to meet 2020
net zero energy targets for existing buildings? ~15,000 MW
CPUC, California Long-Term Strategic Energy Efficiency Plan, January 2011 update
Target: 25% of existing residential reaches 70% reduction
by 2020
Assume 30% reduction with EE, 40% with PV
Residential rooftop PV requirement = 4,800 MW
Target: 50% of existing commercial reaches net zero
energy by 2030 [assume 25% reach net zero by 2020]
Assume 30% reduction with EE, 70% with PV
Commercial rooftop PV requirement = 9,800 MW
Total 2020 residential/commercial rooftop PV = 14,600 MW
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5. California Gov. Jerry Brown Clean Energy Jobs
Plan – local focus
12,000 MW of local renewable power by 2020,
out of 20,000 MW target
Feed-in tariff for renewables under 20 MW
4,000 MW of new combined heat & power
(can be fueled with biogas or biomethane)
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6. Distributed PV in California – the pace is
accelerating
PV Project Underway Capacity Completion
(MW) date
California Solar Initiative 3,000 2016
Utility distributed PV 1,100 2014
SB 32 feed-in tariff 750 2014
CPUC renewable auction 1,000 2014
mechanism
SMUD feed-in tariff 100 2012
Total committed DG PV ~6,000
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7. What is the California IOU renewable energy plan?
CPUC, 33% RPS Implementation Analysis Preliminary Results, June 2009, p. 87.
J. Firooz, Transmission in Short Supply or Do IOUs Want More Profits?, Natural Gas & Electricity Journal, July 2010.
graphic: Black & Veatch and E3, Summary of PV Potential Assessment in RETI and the 33% Implementation Analysis,
Re-DEC Working Group Meeting, December 9, 2009, p. 10.
Original plan was 10,000 MW of
large-scale, remote solar.
Priority emphasis on new, high
profit (12% ROI) transmission.
Up to $15 billion in new
transmission additions in
California, justified on renewable
energy, if utility plans realized.
Now up to 3,000 MW of
distributed PV, beyond 3,000 MW
in California Solar Initiative, also
in the pipeline: IOU-owned PV,
Renewable Auction Mechanism,
SB 32 FIT.
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8. 10,000+ MW Path 46, passing thru Mojave and Colorado deserts,
has lightest load in West. However, access is uncertain due to
existing proprietary long-term capacity contracts.
Sources: 2005 CEC Strategic Transmission Investment Study; June 2010 WECC Path Utilization Study Part of TEPPC 2009 Annual Report.
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9. Achilles heel of remote central station generation,
whether solar or wind - cost of new transmission
sources: 1) RPS Calculator, 2) J. Firooz, P.E., CAISO: How its transmission planning process has lost sight of the public’s interest,
prepared for UCAN, April 15, 2010.
California Public Utilities Commission calculated
$34/MWh transmission cost adder in June 2009 for
remote renewable generation.
CPUC assumed renewable generation financed over 20
yr, transmission over 40 yr.
Cost adder is $46/MWh if generation and transmission
financed over same 20 yr period (apples-to-apples).
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10. Cost of energy for solar and wind – California
agency analyses
source: Renewable Energy Transmission Initiative, RETI Phase 2B Final Report, May 2010, Tables 4-5, 4-7, 4-8, CPUC 2010 LTPP
proceeding, Long-Term Renewable Resource Planning Standards, Attachment 1, Table 1, June 2010.
Technology Capital cost Capacity Capacity Cost of
factor energy
($) (MW) (%) ($/MWh)
Solar thermal, 5,350 – 5,550 200 24 202
dry-cooled
Fixed thin-film PV 3,600 – 4,000 20 24 138
Tracking 4,000 – 5,000 20 27 135
polysilicon PV
Onshore wind 2,371 utility-scale 33 95
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11. Germany installs residential PV at $4/Wdc, lower
cost than utility-scale solar thermal
source: C. Landen – Sovella AG, Complexity cost and economies of scale: Why German residential PV costs 25% less than US,
presented at Solar Power International, October 2010.
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12. Distributed PV as reliable as peaking gas turbine at
summer peak in California
source: B. Powers, Bay Area Smart Energy 2020, to be released in May 2011.
Top 100 hours of summer peak load in
PG&E territory in 2007.
Correlated to hour-by-hour cloud cover
at Oakland and San Jose airports.
Correlated to hour-by-hour global
irradiance for same sites.
Solar resource > 95% available during
all peak hours.
One anomalous data point due to
scattered clouds at airports when rest of
Bay Area nearly cloud free (see GOES
satellite images at right, 3 pm and 4 pm,
July 5, 2007).
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13. Utilities – wind power must be backed-up by
combustion turbines
World without RPS requirements – utilities build
combustion turbines to meet rising peak load.
World with RPS requirements – utilities build combustion
turbines, and wind turbines, and new transmission to
meet rising peak load.
Or central station solar thermal or solar PV, and new
transmission.
Or distributed solar PV (ideally with limited 2 to 3 hr
energy storage), and no new transmission.
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14. Germany – the gold standard
source of 7,400 MWdc in 2010: Renewable Energy World, New Record for German Renewable Energy in 2010, Germany , March 25, 2011.
source of 50,000 MW distributed PV projected by 2020: DENA Grid Study II – Integration of Renewable Energy Sources in the German Power
Supply System from 2015 – 2020 with an Outlook to 2025, April 2011.
7,400 MWdc distributed PV installed in 2010
60 percent less than 100 kW
80 percent less than 1 MW
1,550 MWac of wind installed in 2010
50,000 MW distributed PV projected for 2020
Framework for success: feed-in tariff
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15. April 20th 2011, Germany – PV provides 20% of country’s
electricity at mid-day
German source, EEX Transparency Platform:
http://www.transparency.eex.com/en/Statutory%20Publication%20Requirements%20of%20the%20Transmission%20System%20Operators
Installed Jan. 1, 2011:
wind, 27,000 MWac
solar PV, 16,500
MWdc
Graphic:
yellow = PV
green = wind
gray = conventional
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16. April 20th 2011, Germany – PV provides 20% of
country’s electricity at mid-day, wind < 1%
German source, EEX Transparency Platform:
http://www.transparency.eex.com/en/Statutory%20Publication%20Requirements%20of%20the%20Transmission%20System%20Operators
Top graphic – PV
production, >
12,000 MW at mid-
day, weather
conditions clear to
partly cloudy
Bottom graphic –
wind production,
ranging from 2,400
MW at midnight to
400 MW at noon
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17. Western Interconnect 2010 loads a bit higher than German
loads: min 73,000 MW, max ~150,000 MW
Black & Veatch, Need for Renewables and Gas Fired Generation in WECC - Wyoming Infrastructure Authority Board Meeting, Jan 25, 2010.
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18. Status of utility-scale desert solar on public lands –
lawsuits, cancellations, and uncertainty
Solar project Technology MW Status
Ivanpah Power tower 370 lawsuit
Blythe Solar trough 1,000 lawsuit
Calico Dish stirling 663 cancelled
Desert Sunlight PV 550 lawsuit
Lucerne Valley PV 45 lawsuit
Palen Solar trough 500 lawsuit
Imperial Valley Dish stirling 709 cancelled
Genesis Solar trough 250 lawsuit
Ridgecrest Solar trough 250 cancelled
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19. Problem – ARRA projects are going on undeveloped public
lands, not retired ag lands or mining/military brownfields
source of photos: B. Powers and Solar Done Right website: http://solar.ehclients.com/images/uploads/env_impacts_of_lg-scale_solar_projects.pdf
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20. 1,000 MW Solar Millenium Blythe Solar – disturbed ag
land alternative is feasible, ARRA deadline is hurdle
Sept 2010 CEC Decision: http://www.energy.ca.gov/2010publications/CEC-800-2010-009/CEC-800-2010-009-CMF.PDF
Blythe Mesa Alternative
would include a 1,000 MW
solar facility on three non-
contiguous areas totaling
approximately 6,200 acres.
Blythe Mesa Alternative is
potentially feasible and
meets all but one of the
project objectives.
Private parcel acquisition
would likely not occur
quickly enough to complete
permitting in 2010 to qualify
for ARRA funding.
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21. 1,000 MW Solar Millenium Blythe Solar will disturb 7,000
acres of currently undisturbed public land - nearly size of DC
sources: photo of Washington, DC – Google Earth; 7,000 acres of disturbed land - California Energy Commission, Blythe Solar Project
webpage: http://www.energy.ca.gov/sitingcases/solar_millennium_blythe/index.html
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22. Mojave Solar Development Zone proposal, April 2007 – Solar
Millenium suggests brownfields, anticipates siting challenge
source: Solar Millenium public comment, April 17, 2007 IEPR CEC Workshop, Renewable Transmission, Sacramento. See:
http://www.energy.ca.gov/2007_energypolicy/documents/2007-04-17_workshop/public_comments/22RainerAringhoffSolarMillenium.pdf
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23. 550 MW Desert Sunlight in shadow of Joshua Tree
National Park – too big and too close
August 2010 BLM DEIS: http://www.blm.gov/ca/st/en/fo/palmsprings/Solar_Projects/Desert_Sunlight.html
December 2010 CEC Decision: http://www.energy.ca.gov/2010publications/CEC-800-2010-010/CEC-800-2010-010-CMF.PDF
Project site surrounded on three sides by Joshua Tree NP
Disturbed agricultural land nearby in Desert Center (photo)
Large project not appropriate on border of national park
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24. Recommended guidance to Department of
Interior for use in prioritizing 2011 projects
source: California Desert & Renewable Energy Working Group, Recommendations to Secretary of the Interior Ken Salazar on Ways to Improve
Planning and Permitting for the Next Generation of Solar Energy Projects on BLM Land in the California Desert, December 22, 2010
#1 Low Conflict Areas: timely or expedited permitting/
probable permit approval
Mechanically disturbed lands such as fallowed agricultural lands.
Brownfields, idle or underutilized industrial areas.
Locations adjacent to urbanized areas and/or load centers where
edge effects can be minimized.
Locations that minimize the need to build new roads.
Meets one or more of the following transmission sub-criteria:
transmission with existing capacity and substations is already
available; minimal additional infrastructure would be necessary,
such as incremental transmission re-conductoring or upgrades,
and development of substations; new transmission line only if
permitted and no legal challenges.
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25. Signers of December 2010 recommended guidance:
who’s who of utilities, solar developers, NGOs
Lisa Belenky, Center for Biological Diversity
Darren Bouton, First Solar, Inc.
Barbara Boyle, Sierra Club
Laura Crane, The Nature Conservancy
Kim Delfino, Defenders of Wildlife
Shannon Eddy, Large-scale Solar Association
Sean Gallagher, Tessera Solar
Arthur Haubenstock, BrightSource Energy
Rachel McMahon, Solar Millennium
Michael Mantell, Chair, California Desert & Renewable Energy
Working Group
Wendy Pulling, Pacific Gas & Electric
Johanna Wald, Natural Resources Defense Council
Peter Weiner, Solar industry attorney
V. John White, Center for Energy Efficiency & Renewable
Technologies
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26. EPA’s “RE-Powering America's Land” initiative
see: http://www.epa.gov/renewableenergyland/; photo: PV on former landfill, Ft. Collins, CO.
Siting Renewable Energy on
Potentially Contaminated Land
and Mine Sites
EPA is encouraging renewable
energy development on current
and formerly contaminated land
and mine sites.
EPA would be the appropriate
lead federal entity to designate
“low conflict area” sites for utility-
scale solar projects.
Dept. of Interior/BLM is not the
appropriate entity, as many of
these low conflict sites are not on
BLM land.
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27. California is already on the road to a predominantly
distributed PV future
No technical or economic impediments.
PV at the point-of-use is more cost-effective than
remote solar thermal whether or not new transmission
is needed.
Remote PV that does not require new transmission is
comparable in cost to PV at the point-of-use – line
losses negate much of the desert sun advantage.
Hurdles are institutional – investor-owned utility model
has not yet been re-aligned to advance distributed PV,
and regulators are not forcing the issue.
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