Part two of a two-part series.Should you install a solar electric system? If you own a home in a sunny area and plan to live there for quite a while, a solar electric system (also known as photovoltaics) might be a good investment.
Solar electric systems are becoming more common. They used to be found only in remote areas without utility power; now, even urban buildings are installing photovoltaics.
Photovoltaics can produce electricity more cheaply than current utility rates, when calculated over the life of the system. This is called “life cycle costing,” and takes into account not only the initial cost to buy and install the equipment, but also its operation and maintenance. Since there are no fuel costs, photovoltaics save money over time. Life cycle costs are usually calculated over a 15-25 year period.
How cheap is the electricity from photovoltaics? That depends on a number of factors, including the size of the system (big, commercial installations are often cheaper per kilowatt-hour of electricity produced than smaller, household systems) and whether it includes battery storage or is connected to the grid. A number of utility-connected systems, ranging from one kilowatt in capacity to several hundred kilowatts, are producing electricity for $.20 to $.30 per kilowatt-hour—significantly cheaper than utility electricity on all the islands except O‘ahu. A soon-to-be-completed large (over 200 kilowatt) system will reportedly be providing electricity at $.19 per kilowatt-hour.
As has been discussed in previous columns, however, you should minimize the amount of electricity you use before considering a photovoltaic system. Install a solar water heater, use efficient appliances such as those with Energy Star labels, and be frugal in your power use. Then, when you’ve conserved as much electricity as possible, design a photovoltaic system to provide electricity to as much of the remaining load as you can afford.
In partnership with the state’s energy office, the Maui Weekly provides this feature to help Valley Isle homeowners reduce their utility bills and increase their environmental awareness. For more information, visit www.hawaii.gov/dbedt/info/energy.