You think your electric bill is high?

By Kathryn Almony, for Green Life Hawaii

Five percent of Hawaii's County's total electric usage comes from just one customer. Who is this great and powerful consumer with energy bills totaling in the double digit millions of dollars annually? The Department of Water Supply is the largest consumer of electricity in the County of Hawaii, representing 5% of all the power consumed on the Big Island.

The cost for water is so high because most of our supply comes from ground water aquifers that require extensive pumping to reach homes in each district with enough pressure to reach kitchen sinks at some very high Big Island elevations. The level of power required in municipal water systems to transport water to homes is directly linked to Hawaii's high rate of energy use, and 44% of it is wasted through leaky pipes.

You think your electric bill is high?

In the fiscal year ended June 30, 2008, Hawaii County Department of Water Supply totaled an incoming operating revenue of $37.7 million, of which $17,050,520. was accounted for in power bills from Hawaii Electric Light Company to pump water under pressure through the miles of pipe stretching to communities island-wide, from aquifers throughout the districts into homes.

The overall budget to operate the water supply system serving 41,000 customers was $41.1 million, leaving the water department with a revenue shortfall that year. A cost reduction for energy was negotiated with HELCO and implemented in July of 2009, so the energy costs are expected to be reduced for the 2009 fiscal year. But the consumption of power remains exorbitantly high in terms of kilowatt hours on an island beset by persistent drought, but where more rain falls each year than anywhere else in the United States.
read the source

According to a study commissioned by the Kohala Center for the purpose of identifying ways to mitigate waste, conducted by Jeremiah Johnson, of PA Consulting Group and Marian Chertow, Yale School of Forestry & Environmental Studies, "A Systems Approach to Energy Sustainability in Hawai‘i County", identified that in the Hilo area, almost half - 44% of the pumped water supply was being lost through leaks encountered in transport, never reaching the homes farms or businesses it is intended for. read the source

What can be done?

Johnson and Chertow's work revealed five main areas for potential process improvement: repair the most extensive leaks in the water system, create a water conservation policy, develop more storage capacity to prevent the need for peak pumping, institute a pump system maintenance and efficiency program, and install generating pressure reducing valves.

Despite this report and the recommendations made, there is no day-to-day water conservation policy currently in place on the Big Island. Johnson and Chertow mention that increased storage will reduce the need for pumping during peak hours. The more widespread the use of residential rain-fed water supply, the more we can conserve our precious sources of groundwater on the Big Island.

The Johnson and Chertow study recommends the use of easy to implement water conservation programs such as rainwater harvesting in large commercial properties, installation of water re-use systems, creating a progressive pricing scheme that rewards water efficiency, and creating point-of-sale incentives for water efficient appliances. They predict that if a conservation policy were to reduce water demand by 20%, the energy savings would be equal to saving 2 million gallons of diesel.

As pointed out by Tony Persson, Manager of the Waterworks Hawaii Hilo branch, a relatively small 10,000 gallon tank can supply the residential water needs for the average Big Island household, and can be operated at a much lower cost than the county is spending to pump their water to homes. The cost of the energy required to pump rainwater from the catchment tank, typically located within 50 feet of the home is often less than $500. a year and can be far less if the tank is positioned so that gravity is used to assist transportation of the water. Gravity fed water catchment systems can be configured to utilize solar power for the uv sterilization module, pump, and water heater. read the source

According to Persson, a rain-fed residential water system can be easy to install on most property, is simple to maintain and provides the household with an independently managed, economical and sustainable water resource.

While the Department of Water Supply counts 41,000 island households as customers, Dr. Trish Macomber of the UH College of Tropical Agriculture estimates as many as 60,000 islanders get their household water from rain-fed sources. read the source

More importantly, rainwater is not only free of chemicals, additives and pharmaceutical residue, it can free the residents of the County of Hawaii of a 41 million dollar utility bill.