WALLA WALLA -- While park service staff at the Whitman Mission National Historic Site dedicate themselves to preserving the old, the facilities at the mission aren't stuck in the past when it comes to environmentally friendly technology.
In a park tour over the weekend, Bonneville Power Administration Engineer Tom Osborn and Park Service worker and maintenance expert Mert Heidenrich led visitors on a tour of the mission's solar power and composting projects.
Osborn, who helped install the mission's solar panels, led visitors through a tour of the maintenance shop, which has 60 solar panels on its roof. Together, those panels can generate up to 11 kilowatts of energy -- on average the panels produce enough energy to power a typical house. The mission also added 18 additional solar panels -- for an additional 3.6 kilowatts -- above the visitors center in 2008.
"They wanted something that wouldn't affect the historical nature of the park, so we decided to put up solar panels," Osborn said.
Combined, the two projects cost the Mission around $100,000, a price tag the panels should pay back after 15 years of service. According to Osborn, the panels are under a full warranty for 20-25 years, and can last anywhere from 30-50 years with little maintenance. According to Mission employees, the two projects offset about 30 percent of the park's energy use, although that number was calculated before the addition of an irrigation pump.
Although the panels are situated at the Whitman site, the power they produce is not used to power the buildings. Instead, the electricity generated there feeds into the power grid, spinning the mission's energy meters backward. The mission is then given energy credits for the energy it contributes.
So why doesn't the mission just use the energy to power itself directly? Although energies such as solar and wind power have the benefit of emitting no greenhouse gases, they can only produce power when there is sun or wind, which means they cannot provide a steady, 24/7 stream of power.
There is currently no efficient way to store these kinds of energy, so the mission simply contributes the energy it produces directly into the grid. The contribution to the grid means power plants elsewhere can burn less coal -- the largest single resource used to generate electricity in the U.S. -- while the sun is out or the wind is blowing.
Although Osborn said the solar project was a good way to reduce energy costs, he also said smaller adjustments, like improvements to building insulation or lighting efficiency have been the most cost-effective improvements.
"(Before doing solar) they looked at insulation, they looked at lighting -- they used to have the lights on in the visitors centers all the time, now they're on occupancy censors; they used to be incandescent now they're compact fluorescent ... energy efficiency is cheaper than solar, it's a quicker return on your investment."
The mission has also been able to divert 90 percent of its physical waste away from landfills by composting 70-80 tons of waste.
Park employees use a recipe that calls for clippings, branches, weeds, chips and dirt to create compost for park soil. Employees say the secret to good compost is frequent turning, which provides air for the microorganisms involved with breaking down organic materials and also cycles matter to the pile's warm center, where it can be broken down more easily.
Because of its location, mission employees cannot simply till the compost into a soil, because doing so could damage a buried artifact or Native American burial site. Instead, the compost is used to fill gopher holes, or is spread on top of the mission's soil.
According to mission employees, as of January the Department of Interior has mandated tougher standards for reducing carbon emissions and green waste.
Heidenrich said the mission is well on its way to complying, and the mission plans to expand the solar power program after building a 40-by-60-foot building -- with three compost bays and concrete floors -- over the compost area. On the roof of the building, more solar panels will be added.
According to Heidenrich, that project, which is scheduled for 2012, along with the Mission's use of biodiesel fuels, will most likely be adequate to bring the mission into compliance with all agency standards.
Omar Ihmoda can be reached at firstname.lastname@example.org.
A list of events hosted by the Whitman Mission National Hisotrict Site this summer go to: tinyurl.com/2fdawqo