Renewable

Energy Sources

Solar

LATEST DEVELOPMENTS

• PUC eases rules limiting solar, 6/18/10
• Hawaii's biggest solar farm proposed for Mililani fields, 5/27/10
• Hawaiian Electric utilities again in top ten nationally for solar power, 5/18/10
• Hawaiian Electric & Sacramento Municipal Utility share solar grant, 4/8/10
• Solar installations continue uninterrupted on all islands, 2/26/10

Solar Energy

The sun’s energy can be harnessed with many solar technologies:

Photovoltaic (PV) or solar electricity uses cells made up of semi-conducting materials such as silicon to turn sunlight into electricity. PV cells are combined into modules or solar panels and can be integrated into a solar electrical system to power appliances and electronic equipment.

Federal tax credits of 30% are available to partially subsidize PV systems which can cost $15,000 or more for a typical residential system without battery backup. The State of Hawaii’s 35% tax credit cap for single-family residential PV systems is $5,000, while commercial photovoltaic systems are now eligible for credits up to $500,000.  The State also has a refundable tax credit option.  PV-equipped homes and businesses that are connected to the utility grid and produce more solar electric energy than they use at times can offset their electricity bills with this surplus solar power. This is called net-energy metering and is applicable to PV and other renewable energy systems up to 100 kilowatts in size. It is necessary to sign up with the utility and arrange for installation of a new two-way meter to take advantage of net energy metering.

PV Basics:How PV works and more – U.S. Department of Energy

Concentrating solar technologies utilize concentrated sunlight to produce electricity directly (concentrating photovoltaic) or by capturing heat (solar thermal electric).

Solar thermal electricity is typically produced using curved mirrors which can turn to follow the course of the sun during the day. The mirrors focus the reflected sun’s heat on a tube that contains a heat-absorbing working liquid.  The heat is then transferred from the working fluid to water to generate steam used to turn a turbine similar to a conventional steam generator. A thermal energy storage system can be utilized to store heat, thus allowing electricity production into the evening and after the sun goes down.

On Hawaii Island, Holaniku is Hawaii’s first concentrating solar power project built by local company Sopogy. The 500-kilowatt solar farm is comprised of 1,000 solar collectors spread across four acres at the Natural Energy Laboratory of Hawaii Authority at Keahole Point. Watch our latest tv ad on the Sopogy project.

For more on concentrated solar power, click here.

Solar water heating or solar thermal devices use heat from the sun to produce hot water. From 1996-2009, Hawaiian Electric, Maui Electric and Hawaii Electric Light companies encouraged homeowners to install solar water heating systems through a program that awarded cash rebates tohelp defray installation costs. Customers who also qualified for State and Federal tax credits were able to dramatically lower solar water heating installation costs. The Hawaii utilities led one of the largest and most successful solar water heating programs in the nation.  In 2009, the company achieved a milestone 50,000 solar water heating installations before the program was transitioned to a Public Benefits Fund administrator selected by the Hawaii Public Utilities Commission.

Starting in 2010, a new law requires all new homes to be equipped with solar water heating as original equipment.

Solar Water Heating Basics– U.S. Department of Energy

Solar Energy Technologies Program – U.S. Department of Energy