Delaware’s Renewable Portfolio Standard (RPS) is intended to increase use of renewable resources in the state by establishing the minimum amount of renewable energy that the state's electricity providers must sell in a given year. This legally-established renewable energy procurement goal gradually increases over time to meet the overall target of 25% renewable power by 2026.
The state profile below explores the design of this policy, highlighting the factors that influence the success of Delaware’s RPS goals and the tradeoffs inherent to it. Once you’re comfortable with the information on this page, you can evaluate the policy’s expected viability with the RPS Feasibility Calculator. You can also use the calculator to change the policy requirements, trajectory, cost cap, and more, to see how altering Delaware’s policy design affects its success.
- 25% of the state's retail electric sales from must be from renewable sources by 2026, subject to the cost cap
- Carve-out for solar
- Explicit cost cap at 3% of retail rate
Carve-outs can create economic opportunities in the state by introducing new or promising technologies into the market. However, these standards limit the utilities’ ability to substitute between renewable energy sources, potentially increasing the cost of the policy. Delaware's RPS requires utilities to procure 3.5% of the total energy sales by 2025 with power from solar photovoltaics (PV). This carve-out has its own trajectory, growing from 0.011% in 2008 to 3.5% of sales in 2025.
Compare the goal established in the RPS to what is being achieved.
The following chart compares the variety of sources currently used to generate Delaware’s electricity. The color of each bar is indicative of the carbon intensity of each source.
Cost Cap Details
Delaware has an explicit cost cap at 3% of total retail electricity costs during the same year. (26 Del. C. § 363(f)) For PV the cost threshold is 1% of total retail electricity costs during the same year. Compliance schedules can be frozen at the discretion of the State Energy Coordinator and PSC if these caps are exceeded. Similarly, municipal and rural electric cooperatives have a defined percentage of 4% change in the average customer’s monthly bill.
Historic retail prices (¢ / kWh)
The above chart presents historical data from the Energy Information Administration (EIA) on the price at which residential customers can purchase electricity. Typically, states set explicit cost caps relative to the retail price (as opposed to the lower wholesale price).
The state’s first RPS was established in 2005, requiring 10% of electricity to be from renewables by 2020. The statute would be amended twice in 2007 and 2010 to its current form of 25% renewable electricity by 2026, 3.5% of which must be from solar. These same 2010 amendments provided for Municipal Utilities and Rural Electric Cooperatives to have the option to opt out of the RPS requirements provided they establish a comparable self-directed RPS. The RPS is administered by the Delaware Public Service Commission (PSC).
RPS Technical Details
|Eligible Technologies||Solar electric, wind, ocean tidal, ocean thermal, fuel cells powered by renewable fuels, hydroelectric facilities (max. 30 megawatts (MW)), sustainable biomass, anaerobic digestion, landfill gas|
|Geographic Eligibility||Providers may purchase RECs within the PJM region to count toward compliance. The RECs have a 3-year lifetime. There are credit multipliers for several specific technologies located or manufactured in Delaware|
|Percent of Total Load||70%|
|Technology Requirements||Solar PV—3.5% by 2025|
|Sectors||Investor-Owned Utilities, Retail Electric Suppliers, Municipal Utilities, and Rural Electric Cooperatives|
|Penalty||The ACP schedule increases with each year it is used. For the first year, utilities must pay $25 per MWh of shortfall. This increases to $50/MWh and $80/MWh for the second and third years. The solar ACP is also use-based, set at $400/MWh for the first year, increasing to $450 then $500. State Energy Coordinator has the authority to review and adjust the ACP and solar ACP given certain market conditions. The ACPs are deposited into the Delaware Green Energy Fund. These costs can only be recovered from customers in the instance that the ACP is the least cost measure as compared to purchasing renewable energy for compliance (26 Del. C. § 358(f)(2))|
Tools and other links
- Database of State Incentives for Renewables & Efficiency (DSIRE) RPS data page—Datasets available for download in .xlsx format
- National Renewable Energy Laboratory (NREL) Energy Analysis Portal—Resources on renewable energy policies, and interactive web tools
- Energy Information Administration (EIA) U.S. Energy Mapping System—An interactive energy resource map with a myriad of data layers to explore
- DSIRE State RPS Page—Visit for detailed information on RPS and complete legislation
- U.S. Department of Energy Office of Energy Efficiency and Renewable Energy (EERE)—State Profile—Access your state’s EERE page, and find information on renewable resources maps, energy statistics, and news
- 26 Del. C.—Delaware’s complete RPS statute