Renewable energy
- The Council of the District of Columbia enacted the Renewable Energy Portfolio Standard Act on January 19, 2005, and established a renewable energy portfolio standard ("RPS''}, through which a minimum percentage of District electric providers' supply must be derived from renewable energy resources beginning January 1, 2007.
- The RPS minimum requirements, among other things, were amended by the Clean and Affordable Energy Act of 2008. Further changes to the RPS program were enacted when the Distributed Generation Emergency Amendment Act of 2011 became law. Additional amendments to the RPS program became effective on April 30, 2015, as a result of the Renewable Energy Portfolio Standard Amendment Act of 2014. Complete details can be found on the Commission’s website at http://www.dcpsc.org/Electric/Renewable.asp.
- Renewable energy resources are divided into two categories, Tier I and Tier II, with Tier I resources including solar energy, wind, biomass, methane, geothermal, ocean, and fuel cells, and Tier II resources including hydroelectric power other than pumped storage generation and waste-to-energy. Although minimum percentage requirements are specified for Tier I and Tier II resources, Tier I resources can be used to comply with the Tier II standard. In addition, a minimum requirement is carved out specifically for solar energy.
- As of April 19, 2016, there are 4,545 renewable generators approved by the Commission and eligible to participate in the District's RPS program. Of the facilities approved, 4,516 (99.4 percent) use Tier I resources (including biomass, methane from landfill gas, solar, and wind) and 29 (0.6 percent) use Tier II resources (i.e., hydroelectric).
Demand response
Demand Response programs are designed to reduce power demand on the electric system during times of peak usage like the hottest summer days. Demand response programs benefit all consumers by easing prices in wholesale markets during peak demand and reducing the need for costly upgrades to the electric distribution system.
- The PSC approved a Residential Air Conditioner Direct Load Control (“DLC”) Program in November 2011. Pepco implemented this DLC program during the summers of 2012 through 2015.
- Pepco installed DLC devices for more than 25,000 residential customers in the District.
- The Commission approved the Company’s proposal for Phase II of its program. The Commission also directed Pepco to continue to monitor wholesale market changes in order to file any necessary reform proposals.
Energy efficiency
Energy efficiency programs reduce the amount of energy used by homes and businesses to produce comfort, services, and goods. Energy efficiency can mean financial savings for consumers and businesses while also helping to reduce the environmental costs of producing energy.
- The District of Columbia Sustainable Energy Utility (“SEU”) helps District residents, businesses, and institutions save energy and money through energy efficiency and renewable energy programs. Led by the Sustainable Energy Partnership and under contract to the Department of Energy and Environment (“DOEE”), the SEU is committed to environmental preservation, community engagement, and economic development.
- The Commission monitors the work of the SEU through the Commission Chair’s participation as a member of the SEU’s Advisory Board. During the past year, the SEU has focused on energy efficiency for home and business, including educational programs, home energy audits and the Solar Photovoltaic Initiative. The SEU’s Advisory Board has developed a new RFP to determine the SEU contractor for the next five years.
Fuel cells
A fuel cell is a device that converts the chemical energy from a fuel like natural gas into electricity through a chemical reaction instead of combustion. Fuel cells are different from batteries in that they require a continuous source of fuel and oxygen or air to sustain the chemical reaction. Fuel cells can produce electricity continuously for as long as these inputs are supplied.
Cogeneration facilities - (combined heat & power)
Combined heat and power (“CHP”) technology is used to simultaneously generate electricity and useful heat in a single power-generation facility. The overall efficiency of cogeneration is between 65 to 70 percent (from 27 to 45 percent of electricity and 40 to 50 percent of heat energy), compared to 50 percent overall efficiency when heat and power are generated separately. Cogeneration technologies play an important role as a distributed energy source because of the smaller energy loss in the network, reduced congestion in the transmission system, improved quality and reliability of the continuous voltage supply, among other benefits.
Wastewater heat recovery - wastewater thermal energy (WWTE) systems
Wastewater thermal energy (“WWTE”) systems transfer or absorb heat through conductive piping, from wastewater to a working fluid in a closed-loop system. Regardless of above ground temperatures, sewage temperatures remain relatively constant year-round. These systems are completely sealed and odor-free, making them a safe and effective means of tapping into a sustainable energy source. WWTE replaces conventional heating, ventilation, and air conditioning systems, saving significant energy and fresh water.
Anaerobic digestion
Equipment systems called digesters contain dense populations of bacteria that convert the food source into gas. As a result of the hydrolysis process, the digesters can convert more of the solids into gas, making the process highly efficient. Gas collected in the digesters is cleaned and sent to combustion turbines to produce electricity. DC Water operates a system like this at its Blue Plains facility.
Related Cases
- FC 1130 - The Commission's Investigation into Modernizing the Energy Delivery Structure for Increased Sustainability