SATURDAY, JULY 12, 2008
Hawaii Sunshine: Not just for tanning
See that solar water heater in the photo at right? We have one just like it on the roof of our present house, which was built in 1997. In all that time, we have never run out of hot water. There have been times — such as after a spell of three rainy days in a row — when we had to turn the hot water on all the way when we showered instead of diluting it with cold as we usually do, but those instances have been few.
Hawaii, where I happen to live, is a sunny place. Everyone knows that. So I have wondered forever why more of my neighbors don’t install solar water heaters in their homes. Now that energy costs are greater than ever before, it is even more of a head scratcher that so many people in Hawaii still rely on electricity to heat water for their homes, especially since Hawaii currently has the highest electricity costs in the United States.
That situation soon will change, at least for newly constructed homes. On June 26, 2008, Hawaii Governor Linda Lingle signed into law a bill that requires all new homes built after January 1, 2010, to be equipped with solar or other energy efficient hot water systems. Hawaii is the first state in the nation to pass such a law.
“This solar power legislation is another important step in our long-term plan for energy independence in Hawai‘i,” said Governor Lingle. “In addition to solar, it is critical that we continue to develop innovative energy solutions that capitalize on our natural renewable resource advantages in order to achieve our goal of having 70 percent clean energy in Hawai‘i by 2030.”
Here on the Big Island, another step was taken recently toward that clean energy goal at the Natural Energy Laboratory of Hawaii Authority (NELHA) facility in Kailua-Kona, where ground was broken for a “solar power farm.” The facility, near the Kona International Airport at Keahole, will be run by Hawaii-based solar power and technology company Sopogy. The solar farm will not use traditional photovoltaic panels but will instead use new concentrated solar power technology, according to an article about the project in West Hawaii Today.
“If it performs like it’s performed in tests, we will be able to cut the cost of energy for people in Kona by half,” said Sopogy President and CEO Darren Kimura. “As planned, it’s the largest solar project in Hawaii. If we’re successful, we could cover from here (NELHA) to the airport with solar panels and power Kona.”
The new facility will use a technology, called MicroCSP, which was developed in Hawaii for local conditions. The technology already has been tested successfully at some Hawaii hotels.
Mr. Kimura explained that, while Hawaii gets lots of sunlight, its proximity to the ocean — and the resulting humidity — increases cloud cover, which limits the effectiveness of the traditional photovoltaic panels that need direct sunlight. Unlike photovoltaic panels, the MicroCSP collectors concentrate thermal energy, which is present even when there is no direct sunlight.
Traditional photovoltaic panels, which are made mostly of glass, are fragile and can break when storms or strong winds pass over them. Sopogy’s MicroCSP collectors are less fragile, and are designed to flip over at night to prevent damage from wind and rain. Another feature of the MicroCSP collectors is their energy storage capability, which will enable them to provide consistent energy that will not fluctuate.
Sopogy hopes to have the new solar farm operational by the end of this year. Dare I say — this is a bright development for Kona.