West Hawaii Today
Thursday, November 13, 2008 9:35 AM HST
Big Island homes will likely be receiving more solar-generated power starting next year.
Keahole Solar Power, a Hawaii-based company, is currently constructing a 500-kilowatt system at the Natural Energy Laboratory of Hawaii Authority, with plans to begin selling the energy to HELCO sometime in the first quarter of 2009.
The two companies have reached a power purchase agreement and are now awaiting final approval from the Public Utilities Commission.
While HELCO President Jay Ignacio declined to reveal specifics about the deal until it has been approved, he did say it would have a positive economic influence for consumers.
“It’s not linked to the price of oil, so it will have a stabilizing effect on price,” Ignacio said. “(It) is a small facility, so it’s not going to drive the customer’s total bill. But it is a step in the right direction.”
HELCO residential customers paid an average of 43 cents per kilowatt-hour in October. Many estimates have the cost of producing solar energy well below that figure.
“If developers used tax credits, we’ve heard numbers as low as eight cents (to produce a kwh of solar energy),” said NELHA CEO Ronald Baird. “Without that, we’ve been quoted 18, 20, 22 cents.”
Sopogy, a solar solutions partner company to Keahole Solar, is constructing the system, which uses MicroCSP technology to harness solar power in trough-like solar collector panels. The solar power enters the panels and is reflected from precise mirrors onto receivers in which a heat transfer fluid is circulated.
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Ron Baird, CEO of NELHA, talks about the pumping station for the 55-inch pipeline at NELHA, which supplies most of NELHA’s tenants with deep water. – Brad Ballesteros | Special To West Hawaii Today
The fluid then passes through a series of MicroCSP concentrators called an array. This process raises the fluid temperature and achieves a mass flow creating solar process heat, which in turn enables other technologies such as electrical turbines, absorption air conditioning and steam creation.
“Solar energy is clean, it doesn’t use fossil fuels in its production and it’s relatively inexpensive,” Baird said. “And those things are important when considering Hawaii’s future energy needs.”
According to Sopogy officials, the use of solar energy will also reap environmental dividends.
“This will have a real, sizable impact on our carbon footprint,” said Sopogy president and CEO Darren Kimura.
Keahole Solar has been a tenant at NELHA since 2002, and construction on the current unit got under way last year. Company officials were unavailable for comment.
For the Big Island, a place heavily dependent on foreign oil — yet rich in alternative energies — the emergence of a homegrown system comes as welcome news.
“This technology was born and tested right here on the Kona Coast,” Kimura said. “It’s great to see the fulfillment of that vision.”
Solar energy at NELHA
Sopogy is one of two solar companies currently working out of NELHA:
– SolFocus Inc.: The California-based energy provider is currently testing its concentrating photovoltaic array at NELHA.
In the Solfocus system, small bowls collect solar energy and shoot it back to a tiny mirror, concentrating the beam on triple junction cells, which then convert the light to electricity.
“It’s more efficient at changing light into energy,” said SolFocus adviser Roderick Hinman. “The whole goal is to reduce cost and use less solar cell material.”
The triple-junction cells are made up of layers of germanium, gallium arsenide and indium arsenide, which capture light along different areas of the spectrum.
Hinman said the best single silicone material captures about 20 percent of solar energy, while triple-junction cells ensnare almost 40 percent.
The company’s array is made more functional with a new tracking system that automatically adjusts its panels with the sun for increased efficiency of solar capture.
SolFocus is developing a 2.5 kilowatt-hour array that will be used to partially power NELHA’s Gateway Center, with plans to install three larger arrays next year.