A Million Solar Roofs for Colorado

A Big, Bold Plan to Protect Our Environment and Grow Our Economy

As one of the sunniest states in the country, Colorado has great potential for solar energy. By 2030, Colorado could install solar energy capacity equivalent to that of a million solar rooftops—reducing our dependence on fossil fuels, addressing global warming and boosting our economy.


Environment Colorado Research & Policy Center

Exectutive Summary

As one of the sunniest states in the country, Colorado has great potential for solar energy. By 2030, Colorado could install solar energy capacity equivalent to that of a million solar rooftops—reducing our dependence on fossil fuels, addressing global warming and boosting our economy.

Colorado can install a million solar roofs—or at least 3,000 MW of solar energy capacity—by 2030.*

  • Denver has sunny skies 245 days of the year, and Colorado as a whole has a better solar resource than many places in California, the nation’s solar leader.
  • Colorado has a lot of empty rooftop space. Installing solar photovoltaic (PV) panels on every available and appropriate rooftop space in Colorado would yield more than 16,000 MW of solar capacity by 2030. With the right policies in place, Colorado can develop at least 3,000 MW of this capacity—the equivalent of installing one million rooftop solar energy systems.
  • Community solar projects and utility-scale solar energy can further expand solar capacity in Colorado, providing hundreds of additional megawatts of capacity in the near term and thousands of megawatts over time.

By 2030, solar power can help Colorado avoid 3.6 million metric tons of global warming pollution annually—equivalent to taking 760,000 of today’s passenger vehicles off the road.

  • Preventing global warming pollution is critical to protecting our treasured ecosystems and way of life. Global warming could increase average global surface temperatures by as much as 11°F by 2100. Temperature increases on this scale would reduce winter snowpack, threaten urban and rural water supplies, interfere with agriculture, threaten the state’s forests with more frequent and intense wildfires and insect infestations, and shrink wildlife habitat.

Increasing solar power would help protect public health by reducing harmful air pollution from the state’s fossil fuel-fired power plants.

  • Colorado’s coal- and natural gas-fired power plants harm public health by emitting smog-forming pollution. In 2013, Fort Collins and Denver received “F” grades from the American Lung Association for high levels of ground-level ozone, a key element of smog; Colorado Springs received a “C” grade.
  • In 2030, a million solar roofs (or at least 3,000 MW of solar energy capacity) would help the state avoid 11.8 million pounds of smog-forming nitrogen oxide pollution from power plants annually—a reduction of 9 percent below 2012 power plant emission levels.

Solar power can help speed Colorado’s transition to a clean energy economy.

  • There are already 266 solar energy companies employing 3,600 people in Colorado—placing Colorado sixth in national rankings for total number of jobs in the solar industry and seventh in jobs per capita.
  • The largest area of solar employment in Colorado is in system installation, according to the Solar Energy Industries Association (SEIA). These jobs cannot be outsourced, and as the solar industry grows, so will local employment.
  • Altogether, the solar industry contributed more than $1 billion to Colorado’s economy over the past three and half years, according to a report by the Denver Post.

State leaders should set a goal of installing one million solar rooftops—or at least 3,000 MW of solar energy capacity—by 2030. At least half of this capacity should come from distributed, small-scale solar PV systems to ensure a robust, self-sustaining solar energy market for the long term. The state should also establish a goal of installing 250,000 residential and commercial rooftop solar water-heating systems by 2030.

Reaching this goal will require ambitious policies to promote both small-scale and large-scale solar energy systems, as well as a sustained commitment to strengthening these policies in the long term.

To promote development of Colorado’s solar energy market, policymakers should:

  1. Strengthen the state’s renewable energy standard: The state should strengthen its renewable energy standard (RES) for all utilities by requiring them to get 50 percent of their electricity from renewable sources by 2030. Included in the standard should be a requirement that 10 percent come from distributed renewable energy sources, which will boost development of small-scale and onsite renewable projects such as rooftop solar energy systems.
  2. Strengthen net metering policies: The state’s net metering policies require investor-owned utilities to credit customers who produce electricity through rooftop solar panels at the retail rate for every kilowatt-hour they supply to the grid. Colorado should require that customers of municipal and cooperative utilities be reimbursed at the retail rate, as well. 
  3. Make solar energy an attractive investment for all customers: Colorado should require utilities to work with solar developers to create long-term contracts to purchase solar power from local providers at a fixed rate, which helps eliminate the financial uncertainty caused by fluctuations in electricity prices and guarantees solar energy producers a reasonable return on their investments. The state should also offer more financing options that make solar energy cost-competitive with traditional fossil fuels. 
  4. Develop Colorado’s potential for solar water heating: Solar water-heating systems have the potential to reduce household energy use for water heating by about 60 percent, but they are not widely used because they have higher up-front costs than natural gas water-heating systems. The state should create an incentive program to bring down the cost of installing solar and other renewable energy water-heating systems and include renewable water-heating technologies in residential and commercial natural gas efficiency programs. 
  5. Renew tax exemption programs: Colorado exempts renewable energy products—such as solar panels, mounting equipment and wiring—from sales and use taxes. The state should extend these exemptions beyond their 2017 expiration date, guaranteeing the incentives for at least 10 years.
  6. Support community solar projects: Community solar gardens allow residents to pool their resources to establish community solar arrays, and to offset their electricity use through group net metering. By fall 2013, Xcel Energy’s community solar program is expected to bring online 9 MW of solar capacity in 13 solar gardens across the state. Xcel should continue approving solar gardens at this pace, and other utilities should follow suit. 
  7. Eliminate regulatory barriers to the expansion of solar energy: State and local leaders should work to standardize procedures, minimize fees, and streamline the process of installing a new solar energy system and integrating it into the electricity grid to make it as easy and affordable as possible for Coloradans to participate in the solar market.
  8. Create a net-zero energy building code: A net-zero energy building code requirement would increase the use of solar and other local clean energy systems in new construction. Colorado should require all new homes to include solar power or other on-site renewable electricity generation by no later than 2020, and all non-residential buildings by no later than 2030, through a net-zero energy building code requirement.

*For the purposes of this report, we assume rooftop solar energy systems to be 3 kW (DC) in size.