The cost of renewable energy has been quickly dropping and renewable energy generation has been rapidly growing in the United States, spurred by state and federal policies and technological advances, said a new report, dated June 2016, released by the White House Council of Economic Advisers.
Moreover, projections going forward suggest ever increasing penetration of renewables into the electricity grid. The two most rapidly growing renewable energy sources, wind and solar, provide variable energy output that depends on the time of day, location, season, weather, and other factors, the report noted. Integrating high levels of these renewables onto the grid will require a reimagining of the management of the grid. It will increase the demand for grid management services, opening up a new set of important opportunities for promising technologies and approaches.
This report examines economic and technical considerations related to increasing integration of variable renewable energy resources onto the existing electric grid, which highlight the importance of emerging technologies and approaches in smart markets and energy storage that can help smooth this transition. Smart markets use new communications technologies to develop integrated approaches allowing for electricity demand to respond during times of high value. Energy storage technologies allow the temporary storage of electricity so it can be released during times of high value.
The federal Recovery Act was the largest investment in history in clean energy, spurring private sector innovation and investment in new technologies around the country. The CO2-reducing Clean Power Plan (which is currently tied up in federal court), the production tax credit and the investment tax credit all promise to continue facilitating further growth in renewable energy markets in the coming years, the report said.
For many years, state renewable energy policies have successfully deployed renewable energy across the country. In addition, President Barack Obama has joined the leaders of 19 other countries and the European Union, representing over 75% of the world’s CO2 emissions from electricity, in “Mission Innovation,” a commitment to double clean energy research and development over the next five years.
Wind and solar generation accounted for 5.3% of total U.S. electricity generation in 2015, more than doubling from under 2% in 2009. Moreover, they are expected to continue growing rapidly, especially with considerable price declines of 80% for utility-scale solar and 60% for wind since 2009. As the penetration of renewables, with their highly variable outputs depending on wind and sun conditions, reaches much higher levels, their distinctive features will require a re-envisioning of the management of the grid.
For example, the report said that some energy analysts and academics have long argued that wind and solar combined can never reach more than 15% to 20% penetration into the grid due to the need to meet demand at all times and ramp up and down other resources to balance intermittent ones. However, said the report, there is evidence of much greater penetration of renewables in some regions. For instance, Texas hit a record level of instantaneous penetration from wind generation during one evening in February of this year, with wind energy providing 45% of total electric power.
Internationally, penetration of variable electricity as a percent of total annual electricity consumption reached high levels in many countries in 2015, such as 42% from wind in Denmark, 24% from wind in Ireland, and 23% from wind in Spain, with instantaneous generation rates at times exceeding 100% of electricity usage in some of those nations. Earlier this year, Portugal ran for four days straight on 100% renewables (wind, solar, and hydropower).