For the average Kaua‘i resident, monthly electricity bills can be a tough pill to swallow. Rising oil prices and the island’s isolation, among other factors, have ensured the relatively high cost of powering a home. Conservation and smart use —
For the average Kaua‘i resident, monthly electricity bills can be a tough pill to swallow.
Rising oil prices and the island’s isolation, among other factors, have ensured the relatively high cost of powering a home.
Conservation and smart use — turning off lights after leaving a room and replacing traditional light bulbs with compact fluorescents — are key to chipping away at the bill, but they can only go so far.
Photovoltaics and wind generation systems, on the other hand, can produce enough energy to take a home “off the grid,” but the cost to install them runs in the tens of thousands.
So what is the happy medium for the consumer who’s willing to invest a little in order to save a lot?
The answer: solar water heaters.
Swapping out a traditional, electric water heater with the solar variety can cut a residential electric bill almost in half, according to Kaua‘i Island Utility Cooperative.
“If you put in a solar water heater, you took a first good step to addressing the biggest part of the (electric) bill,” Ray Mierta, energy services supervisor with KIUC.
According to Mierta, about a third of the island, or 7,000 residential customers, have already gone solar. And thanks to KIUC incentives as well as federal and state tax credits, installation is more affordable than it used to be.
Compared to the $25,000 to install a full solar system, $6,000 to $7,000 for a solar heater seems like a drop in the bucket.
Maria Spencer, director of sales and marketing for Sun King Inc., said factors that influence the cost of a unit include the size of the family, size of the home and location of the home.
She advises customers to educate themselves on the different options and hire a knowledgeable contractor.
“People call on the phone and think they are going to get a pair of shoes,” Spencer said, “but they really have to try on the shoes.”
The two main types of solar heaters — passive and active — differ in how they circulate water through the photovolatic cells, which heats it.
Passive systems rely on gravity to move the water, and usually the storage tank is located on the roof with the solar panels. Active systems, on the other hand, use an electric pump to move the water from the collectors to the tank on the ground.
An even cheaper alternative, though not a solar one, are heat pumps, which take advantage of Hawai‘i’s hot climate by using warm air to heat water. The pumps run on electricity, but require two thirds less energy than an electric water heater. They are also about half the cost of a solar heater, according to KIUC.
As for the lifespan of the solar thermal technology, Mierta said it is extremely reliable and easily adapts to most residences.
“We’re seeing solar heaters that were put in 20 or 30 years ago and they’re still working fine,” he said.
KIUC offers an $800 rebate and a no-interest loan for customers who work with approved companies.
In addition, the state provides tax credits for 35 percent of the installed cost.
For more information, visit www.kiuc.coop or www.hawaii.gov/dbedt/info/energy/renewable/solar
Water heater alternatives:
• Heat pump (non-solar): A pump that takes advantage of Hawai‘i’s hot climate by using warm air to heat water. They use about one third the energy of a traditional water heater.
• Active system (solar): Water storage tank located on ground; pump required to circulate water through solar panels.
• Passive system (solar): Storage tank is on roof; no pump required to circulate water through solar panels.
