Grid-tied Renewable Energy Electric Systems

HVAC | Plumbing | Electrical | Ductwork | Solar Hot Water Heating Systems | Grid-tied Renewable Energy Electric Systems

A grid-connected power system allows a home to get part or all of its electric power from renewable sources, and reduces demand on existing coal, oil, gas, hydroelectric, and nuclear generating plants. New laws called “net metering” allow electricity consumers to connect battery-less PV energy systems to the utility grid. When a renewable energy system is generating more power than it is using, the excess feeds back into the grid, resulting in a reduction in the utility bill. The electric meter spins backward, “banking energy” as a credit for future use.

Renewable energy use for electrical generation is an area of construction that YouthBuild programs have typically avoided. The installation and maintenance of these systems is not especially difficult or complicated, but should be learned from a professional and installed by a commercial installer. A qualified installer will help design and build a system that not only meets the needs of the project, but meets the National Electrical Code and functions safely.

Renewable energy use should only be considered once a program has had success in building energy-efficient homes. When sizing a renewable energy system, even the smallest amount of wasted electricity can result in huge cost differences as solar electric panels are added to systems in series, meaning that depending upon the wiring, you may have to add two or more panels to the system even if your electric load would only require one additional panel. The high initial cost of renewable energy electric systems require a builder to reduce the electric loads as much as possible. The biggest electric loads in residential homes are refrigerators, washers and dryers, and appliances that produce heat such as irons and coffee pots.

Implementation of Grid-tied Renewable Energy Electric Systems

• Contact the local utility company to see if they will allow a connection of a solar system to their electrical grid.
• If the utility company will allow the connection of a PV system to their grid, the next question to ask is if they will buy the energy back at the retail or wholesale rate.
• Identify a qualified renewable energy installer. You can find an installer in the Off-Grid Living Web site under the Resources section.

Benefits of Grid-tied Renewable Energy Electric System

• Allow inhabitants to lower electric bills and have access to a very reliable source of power.
• Grid-tied renewable energy systems will lower electric bills, and, as electricity costs increase, the payback time for a system decreases.
• Renewable energy systems immediately contribute to a cleaner planet.
• Homeowners can access numerous rebates through the federal government and various state and local programs. (See the YouthBuild Green Pages for listings.)
• Builders can access numerous incentives through the federal government, various state and local programs, and private sources of funding.

Challenges of Grid-tied Renewable Energy Electric Systems

• Initial costs will vary greatly depending upon the size of the system and amount of labor costs.
• Homeowners need to learn proper maintenance of system, particularly if there is a battery bank.

CASE STUDY

Old Colony Y YouthBuild Brockton celebrates as a first-time homeowner is handed the keys to a four-star Energy Star-rated home built by the programYouthBuild Brockton uses Energy Star Ratings to Build Affordable and Sustainable Homes

Since 2001, YouthBuild Brockton, Massachusetts, has built five Energy Star-rated homes and is currently working on one unit in partnership with Habitat for Humanity and a seventh unit in partnership with the Boston Housing Authority. John Bengel, executive director of the Brockton program, emphasizes that the importance of the Energy Star Program is two-fold: The program promotes energy-efficiency and environmental responsibility in construction, and it provides affordability for the homeowner

According to the U.S. Environmental Protection Agency Energy Star Web site, “homes that earn the Energy Star must meet guidelines for energy efficiency set by the U.S. Environmental Protection Agency. Energy Star-qualified homes are at least 15 percent more energy efficient than homes built to the 2006 International Energy Conservation Code (IECC).” The Environmental Protection Agency (EPA) reports building homes that use substantially less energy for heating, cooling, and water heating can reduce maintenance costs $200–400 annually. The Energy Star program measures efficiency for the entire home, not just retail appliances. Features that are also rated include increased insulation, tight building construction and ducts, and energy-efficient window and building envelope.

Bengel reports that using Energy Star-rated insulation and appliances increased construction costs only 2 to 4 percent. The Energy Star program does have an application fee that can be waived. After house plans and specifications are complete with Energy Star features, the EPA representatives evaluate the plans to assign an Energy Star rating and consult the construction team to implement improvements on the submitted plans. Bengel describes the application process as supportive and fairly easy to implement. Besides producing efficient, affordable homes, builders can apply for rebates based on their level of energy efficiency. Bengel says that, with a 92 percent rating for the YouthBuild constructed homes, the rebate program covered nearly half of the costs of the appliances by using efficient forced hot-air furnaces, more insulation, and installing Energy Star-rated appliances and lighting.

“The Energy Star program promotes homeownership by creating homes that are less expensive to operate,” says John Bengel.

For more information, contact Mark Showan, program director at YouthBuild Brockton.

> Find out more about the Energy Star program and associated rebates within your state