According to ASES’s pioneering report: Green Collar Jobs in the U.S. and Colorado – Economic Drivers for the 21st Century, the renewable energy (RE) and energy efficiency (EE) industries generated more than 9 million jobs, more than $1 trillion in revenue, and nearly $160 billion in federal, state, and local tax revenue in 2007. Our report determined:
“If U.S. policymakers aggressively commit to programs that support the sustained orderly development of RE & EE,” these RE & EE industries could “generate up to $4.3 trillion in revenue in the United States and create more than 37 million jobs by the year 2030” – that’s 17 percent of the U.S. work force. To follow are solar electric and solar thermal installation figures.
PHOTOVOLTAICS
Photovoltaic cells are semiconductor devices that generate electricity when exposed to the sun.
Manufacturers assemble the cells into solar modules which can be installed on roofs or walls, or
on ground-mounted arrays. PV was invented in the United States in the 1950s, and was first used
to power satellites.
U.S. Deployment – Grid-connected PV installations in 2009 grew by 40 percent to 435
megawatts (MW) DC, bringing total installed grid-connected capacity to 1.25 gigawatts (GW)
DC. In 2009, solar PV was installed at more than 33,000 sites, a 76 percent increase over solar
electric systems installed in 2008, and four times more than the amount of solar electric installed
during 2006.
Residential – Installations in homes accounted for 36 percent of solar PV growth in 2009 (see
figure 1.) The residential sector’s market share was significantly higher than the 27 percent
market share in 2008.
Non-Residential –This sector, which includes government buildings, military installations, and
retail stores, accounted for 49 percent of solar installations in 2009. Unlike 2008, where non-
residential installations were the largest solar sector, the non-residential sector had flat growth in
2009.
Utility-Scale –This area includes installations for bulk utility-scale power production. Utility
installations tripled in 2009, comprising 15 percent of grid-connected PV systems installed in
2009. Two noteworthy PV projects installed in 2009: a 25 MW facility in Florida and a 21 MW
project in California.
State View – Grid-tied PV systems installed in 2009 were concentrated in five U.S. states in
order of rank: California, New Jersey, Florida, Colorado, and Arizona (see Table 1). The solar
electric market more than doubled in New Jersey, Florida, Arizona, Massachusetts, and Texas,
with Florida moving up from 16th place to 3rd place for installed PV installations due to the 25
MW utility-scale project mentioned above. California has the highest total PV capacity per capita
of 20.8 watts -dc/person – almost five times the national average of 4.2 watts per capita (see
Table 2).
SOLAR THERMAL
Low-temperature solar thermal collectors produce heat for hot water for domestic or commercial
use, for space heating to heat and cool buildings, and to heat swimming pools and spas. A variety
of flat plate, evacuated tube, and concentrating collector technologies produce the heat needed
for these applications.
U.S. Installations – According to the Solar Energy Industries Association (SEIA), the solar
water-heating market grew 10 percent in 2009, compared to a 40 percent increase in 2008 and a
26 percent increase in 2007.
Solar Hot Water & Space Heating – Hawaii is the dominant state in the solar hot water market,
accounting for 27 percent of solar hot water installations in 2009 (see Figure 3). Based on data
from the Energy Information Administration (EIA), prior to 2006, about half of annual solar
water heaters sold in the U.S. were in Hawaii. By 2008, installations outside Hawaii increased by
seven times. After Hawaii, the leading states for solar water-heating installations are California,
Puerto Rico, Florida, and Arizona (see Figure 4).
Solar pool heating – Annual installed capacity for solar pool heating systems fell by 1 percent
from 2007 to 2008. This is an upswing as compared to a decline of 15 percent in solar pool
heating capacity from 2006 to 2007. Florida and California are the largest markets for solar pool
heating and solar pool sales have declined for three straight years due to the weakened real estate
market in these two states (see Figure 5).
CONCENTRATING SOLAR POWER
A recognized growth area for solar energy is high-temperature solar thermal electric-generating
systems, more commonly known as concentrating solar power (CSP) plants. These plants
are based on mature technology, using mirrors and collecting receivers to heat a fluid to a high
temperature (300°F to more than 1,000°F) and then run the heat extracted from the fluid through
a traditional steam turbine or a Stirling engine to spin an electric generator. CSP can be paired
with existing or new steam-turbine or gas-turbine power plants, providing high-temperature heat
into the thermal cycle. These generating stations produce base load power on the utility side of
the meter.
The Southwestern United States has several CSP plants in deployment. The 354MW SEGS
(Solar Energy Generating Stations) in California’s Mojave Desert have been producing power
for the grid reliably and profitably since 1991. Nevada Solar One, generating 75MW, came on
line in 2007. Xcel Energy commissioned a 45MW array in Grand Junction, Colo. this summer.
A number of CSP plants are scheduled to go on line beginning in 2011 in the Southwest and
Florida. A few of these plants incorporate molten-salt thermal storage systems to enable electric
power generation late into the evening hours.
“We see CSP plant technology, with built-in storage capacity, as one of the major renewable
energy solutions to sustainably replace fossil fuels and provide proven large-scale solar powered
electricity to the electrical grid 24 hours a day,” said Brad Collins, Executive Director of ASES.
2010 PROJECTIONS
“Based on early predictors, we estimate a grid-connected PV growth of 50 to 100 percent in
2010,” said Collins. “However the continued growth of the U.S. solar industry is directly tied to
Congress passing supportive RE & EE government policies. Every day when the sun comes up,
people know that the sun is a sustainable solution to our energy situation. American scientists
started the solar energy industry. It’s time for U.S. businesses and the American people to make
our voices known to move solar to a mainstream energy solution in the U.S.”
For ASES policy recommendations on climate reduction/ clean energy legislation and our Report
Card to the 111th Congress, please visit www.ases.org. ASES grassroots solar advocacy program
based in Washington, DC – Solar Nation – produces free Action Alerts to encourage grassroots
response on the state and federal level.
AMERICAN TECHNOLOGY
Most of the technologies described above were invented and developed in the United States.
American scientists and solar researchers were founding members of the Association for Applied
Solar Energy, launched in 1954. AFASE grew to become both the American Solar Energy
Society and the International Solar Energy Society.
ACKNOWLEDGMENTS
The author credits the data, tables, and figures in this article to the 2010 Interstate Renewable
Energy Council (IREC) report prepared annually by Larry Sherwood. Mr. Sherwood’s report
was first published in Conference Proceedings for SOLAR 2010, the 39th annual ASES National
Solar Conference. The full article Solar Energy Trends is available in the July/August 2010
issue of SOLAR TODAY Magazine with back issues of the magazine available digitally. Mr.
Sherwood, president of Sherwood Associates, is a former Executive Director for ASES.
