What is building electrification?
Building electrification is the process of powering all building appliances and systems with electricity in lieu of fossil fuels (e.g. gas or fuel oil). Building electrification ultimately allows for buildings to be powered by 100% clean and renewable energy, thus reducing our dependence on fossil fuel sources.
Why electrify?
Electrifying buildings is an essential part of decarbonizing buildings, which is an essential step to fight climate change and align with the priorities of the District.
Decarbonization is the reduction or elimination of carbon dioxide from the energy sources we consume for all our human needs. A full decarbonization of all our energy systems is the primary solution to stabilize or reverse climate change. In the District, buildings are responsible for more than 70 percent of greenhouse gas emissions. To decarbonize buildings we must eliminate the use of fossil fuels to power buildings and switch to clean energy sources by shifting to renewably generated electricity and away from energy supplied by oil, gas, or coal. We must also build and retrofit our properties to perform better and be more energy efficient.
Building decarbonization is essential for the District to meet the goals of the Clean Energy DC Plan to become carbon neutral by 2050. This Plan also includes provisions to phase the District’s buildings codes to require that all new buildings be net-zero energy and 100% electric.
Several pathways to decarbonization are feasible today, making the goal of building decarbonization increasingly within reach for building owners. With intentional design and analysis, building electrification can also increase efficiency, cut costs, improve indoor air quality, and enhance safety. This future proofs a building by protecting against the risk that future climate regulations will require you to replace costly combustion equipment ahead of schedule.
What does electrification mean in DC?
The energy used in the District originates mainly from carbon-intense fossil fuels and is supplied by aging infrastructure that is gradually becoming more strained as the population in the city increases and grows more dense. To meet its climate commitments while minimizing the cost of maintaining electric grid reliability, the District must reduce energy consumption and carbon emissions.
The District, energy regulators, and the private sector are actively working together to increase local renewable electricity generation. Currently, only 5.2% of the generation fuel mix for the District’s region (as classified under the U.S. Environmental Protection Agency’s Emissions & Generation Resource Integrated Database) comes from renewable energy sources compared to the national average of 17%. The DC renewable portfolio standard mandating 100% renewable electricity by 2032 is expected to drive down emissions as more clean energy is added to the grid.
In tandem with the grid shifting towards a higher percentage of renewable energy sources, energy efficiency targets for new and existing buildings will also become more stringent. To address both of these concerns at once, electrification options should be evaluated hand-in-hand with energy conservation measures (ECMs) to reduce overall electricity demands before fully electrifying a building. The District’s Building Energy Performance Standards and updated building codes are two policies aimed at reducing energy consumption in buildings.
How and when to electrify
New construction should strive for all electric systems, whereas existing buildings in the DC market should work first on increased efficiency to reduce fuel consumption and then electrify where and when it is practical to do so. Systems to investigate for electrification include:
- Mechanical heating systems (boiler or direct-fired gas heating)
- Domestic hot water systems (water heater)
- Appliances (gas range, gas clothes dryer)
- Backup energy sources (generators)
Key considerations that will impact an existing building’s ability to electrify include:
- Building age. Buildings 10 years or older should be investigated for electrification opportunities. Newer systems and appliances within buildings that are less than 10 years old do not need to be electrified until they are at least 15–20 years old or have reached the end of their useful life. Newer buildings should instead investigate opportunities for increased energy efficiency within the existing building systems.
- Electrical capacity. For existing buildings, the building’s electrical infrastructure will need to be evaluated to determine the available capacity to switch some or all systems from fossil fuels to all-electric sources.
- Physical space allocations. Building owners must evaluate a building’s central plant and shaft space to determine if physical space allows for modifications to systems.
- Fuel source of current domestic hot water, mechanical heating, cooking, and backup energy sources. An existing building may use a combination of natural gas, fuel oil, or electricity to serve these systems. An engineer should assess these systems to determine the feasibility of converting each to electric based on electrical requirements and physical space allocations for each. A viable solution may be to only electrify one or a combination of a few of these systems.
- Anticipated system lifespan and current efficiency. If existing building components and systems are at the end of their useful life or if there has been a significant drop in their efficiency, a switch over to all-electric might be timely. If systems are still relatively new or running efficiently, a transition is likely not appropriate.
Acceptable payback. If a building owner is willing to accept a payback of 10 years or longer, electrification is recommended. Otherwise, opportunities for increased energy efficiency should be investigated instead.
Building components to electrify and available options
Multifamily buildings | Office buildings |
---|---|
Natural gas heating | Natural gas heating |
Natural gas water heating | Natural gas water heating |
Natural gas cooking appliances | Emergency generator |
Natural gas clothes dryer | |
Emergency generator (diesel) | |
*Items listed in typical application greatest to least fuel usage |
Heating Systems
Building electrification provides the opportunity to incorporate energy-efficient solutions and upgrade a building’s control systems to better monitor a building’s energy consumption and reduce emissions. Recommended strategies below outline where fossil fuel sources are most often used in Washington, DC buildings and the opportunity to incorporate electric options.
Gas-fired component. Although they are more commonly found in multifamily residential and educational buildings, boilers used for space heat (and sometimes also combined with water heating) can be found in some commercial buildings in the District.
Electrification replacement options. Mechanical heating options to replace gas-fired boilers include:
- Heat recovery chillers, which provide simultaneous cooling and hot water production for space conditioning
- Geothermal heat pumps, which are less feasible for existing commercial buildings and more feasible for larger campuses or new buildings with yard space for boreholes
- Air-source heat pumps, can provide both heating and cooling needs for a building
Domestic Hot Water Systems
Gas-fired component. Gas water heaters are most commonly found in multifamily residential buildings as either individual units or central systems. Educational buildings and commercial office buildings also have a significant number of central systems (with boosters if needed) that provide hot water demands. Also, while a lower demand in the District, indoor and outdoor pool heating also is a portion of the fossil fuel-dependent water heating demand.
Electrification replacement options. Electric water heaters can be used to replace gas water heaters, and often increase efficiency and save space. Alternatively, if rooftop space allows, solar water-heating systems can be used to offset water heating loads. Options include:
- Individual-unit electric water heaters. Multifamily buildings can implement tankless water heaters appropriately sized for the unit’s water demand.
- Floor-by-floor electric water heaters. Tankless water heaters can be ganged together in a back-of-house location, or commercial systems can be sized to serve an entire building floor’s water demand.
- Central systems. Whole-building electric solutions, such as hot-water heat pumps should focus on efficient piping distribution to minimize heating losses.
- Pool heaters. Heat pumps sized on the gallons of pool or hot tub water can replace gas equipment for year-round solutions.
- Solar thermal water heating. Indirect solar thermal systems can provide seasonal water heating that can be paired with other electric options.
Cooking Appliances
Gas-fired component. Gas-fired kitchen appliances typically include ovens, stoves, ranges, cooktops, and fryers.
Electrification replacement option. Electric cooking equipment delivers heat three times more effectively than gas equivalents, and even more efficiently for induction systems. In commercial kitchens, electric options for ovens are becoming more common for baking, while gas is still more common for cooking. Commercial electric induction cooktops, induction woks, and fryers are market available, but come with a first-cost premium. In residential buildings, the transition is more challenging since residents typically prefer gas stoves. However, switching to all-electric oven, stove, and range appliances provides air quality and health benefits, as gas stoves are a primary source of combustion (burning) pollution inside the home and can spike the level of pollution in a home. Unlike commercial options, residential electric appliances do not have a first-cost premium. ENERGY STAR-rated equipment is also available for residential cooking appliances and commercial food service equipment for further efficiency savings.
Clothes Dryers
Gas-fired component. In multifamily residential buildings, gas clothes dryers are commonly located in individual units and central laundry room locations and are often attributed with the largest appliance energy load.
Electrification replacement option. Converting to an all-electric clothes dryer will increase the efficiency from approximately 30% in gas dryers to over 200% with electric dryers. ENERGY STAR-rated clothes dryers also increase efficiency by including sensor drying and low-heat settings.
Emergency Generator
Fuel oil-fired component. Diesel-powered emergency generators are used for emergency backup power in the event of an outage.
Note: Emergency generators in the District will likely remain fossil fuel powered for the foreseeable future due to physical size restraints and concerns around safety for large buildings (typically 50,000 sq. ft. or larger). The District is planning to make exceptions to its electrification goals and the no-combustion rules set forth in Appendix Z until more viable, market-ready solutions are available.
Electrification replacement options. Alternatives to fossil fuel generators include:
- Battery-stored backup power, which allows for the operation of lights, appliances, and communications systems in the event of a power outage
- Solar-powered generators, which are portable, rechargeable all-electric battery powered units.
What systems need further research and innovation?
As demand is growing for systems with higher energy and water efficiencies in large buildings and lower carbon emissions, newer technologies have varying levels of proven viability. Newer technologies follow the traditional technology adoption curves where investors are hesitant to take the risk on higher first costs without proven returns or upfront rebates or incentives. However, as seen with other technologies such as cellphones and solar photovoltaic systems, higher adoption rates can drive costs down to create a competitive market. The following technologies are expected to see expanded research, innovation, and market adoption in the foreseeable future:
- Commercial kitchen induction cooking equipment.
- Heat recovery of rooms with heat loads (i.e. telecom rooms, electrical exhaust). Redesign mixed use spaces to be able to recover and reuse the heat that is produced by cooling them in another application.
- Hydrogen fuel solutions. Preliminary research and pilot projects show that existing fossil fuel natural gas infrastructure could be repurposed with these zero emission fuel sources.
How “smart building” features can help
New buildings often include advanced, digital infrastructure to improve energy efficiency while also helping to manage electric systems and building components. These “smart buildings” set an example for the industry, incorporating scalable technologies that can be considered for existing building retrofits as well. In order to reach electrification goals, building energy efficiency must be first be improved, and you cannot improve what is not properly managed. Smart technology provides a pathway for this through increased efficiency in the HVAC system, electrical loads, and grid-integrated buildings.