Same Sun, Superior Science

In 2009, the Regulatory Commission of Alaska approved net metering regulations, which went into the effect the following year. These rules allow a customer to install and use certain types of renewable energy while connected to the grid. They can use the renewable energy to offset their monthly energy use and sell any excess power to the utility, which uses it to supply other customers. Homeowners can get credits on their monthly bills during periods of high generation and use those credits to offset costs during the winter months.

Trimble says a typical residential solar setup can cost about $20,000, but tax credits and grants can offset some of the initial costs.

“Typically, we can provide anywhere from 75 to 100 percent of a home’s annual energy with solar in Alaska, which is pretty amazing,” he says. “Most people don’t think we have that much of a resource here.”

Current tax credits, which expire at the end of 2019, can cover up to 30 percent of the initial investment.

“We see solar pay for itself on a home typically between nine and ten years,” he says. “That’s a good solar payback for pretty much anywhere.”

Improvements in Tech

In Homer, veterinarian Dorothy Sherwood turned on a new solar system at her clinic on winter solstice last year, “So the only way was upward from then!” she says. She also has a solar system installed at her home.

The system at her clinic includes two arrays and twenty-two microinverters. To date, it has produced 5.8 megawatt-hours of electricity.

“I wanted to reduce my clinic’s dependence on non-sustainable energy systems, which would not only reduce the clinic’s carbon footprint but ‘walk the walk’ when addressing my concerns regarding climate disruption/change,” Sherwood says. “I think the advantages of solar energy are widely understood… low carbon footprint/reliable source of energy for a large portion of the year, clean energy at installation, and providing business to local solar energy businesses.”

Sherwood also used a grant from the Renewable Energy Alaska Project (REAP) to help offset the initial costs.

Sherwood says a second system at her home includes ten arrays plus microconverters.

“We have worked on creating our home to be as energy efficient as possible over the years, and our monthly electric bill before solar is averaging $80 with two teenage sons in our home,” she says. “We look forward to seeing how solar will provide for our needs into 2019.”

Technology improvements in the past decade are another reason solar and renewable energy is taking off in Alaska, Trimble says. Today’s solar arrays have no moving parts, unlike past systems that required solar sensors that would move the array during the day as the sun passed overhead.

Solar panel efficiencies and capacities have gone up in recent years, and the tracking mechanisms are no longer needed, Trimble says.

“It’s cheaper to add a few more stationary, no-moving-parts panels than to add a tracking mechanism that will require replacement in a few years.”

Battery technology also has improved. Trimble uses lithium-ion batteries in grid-connected solar systems. The batteries can provide power in times of outages or low generation.

“Instead of having a gas generator, you have a battery that is charged from your solar array from excess solar energy,” he says. “That’s a pretty unique concept for Alaskans. It’s basically a generator that’s rechargeable from an unlimited energy source.”

Until recently, battery systems were less stable and required ventilation. Today’s batteries are similar to the batteries used in cell phones, which can be tucked away and don’t require any special handling.

Another advance is the use of module or panel power technologies. In the past, solar panels would be hooked up to an inverter. Since solar produces direct current, the inverter changes it to alternating current, which is what common electronics use. But if one of the panels was blocked, the whole array would go dark.

Today, with the advent of module/panel power level electronics, a device goes under each panel that regulates its power production independently of the others. If a panel is blocked, the other panels will continue to produce power.

“That’s been a really big change for enabling solar power in areas that tend to be more cloudy,” Trimble says. “The technology has also matured a lot since it was introduced—there used to be a lot of equipment failures. Now technologies are very robust and the equipment is warrantied for twenty-five years.”

Trimble says he has installed more than 4,000 devices and none have failed.

And solar isn’t the only renewable energy option for Alaskans.

Wind, Biomass, and Heat Pumps

In rural Alaska, wind farms have sprung up in many villages, reducing their reliance on expensive diesel systems. In Buckland, a large solar array just went online, boosting the village’s wind and diesel systems. In Tanana and Tok, biomass systems are producing energy for schools and village facilities. All of these systems are scaled to work in villages with a few hundred to thousands of residents, says Chris Rose, REAP’s founder and executive director. Rose is looking at a different technology, an air-source heat pump, which works as a kind of “reverse air conditioner” to provide heat for individual homes. It takes outside air and condenses it, which creates heat.

“That’s not renewable energy, but it’s technology that’s super-efficient,” Rose says. “People as far north as the Arctic Circle are now using it. These devices now are so efficient that one unit of electricity that you use to run the pump is getting four units of heat out at certain temperatures.

“The colder it gets, the lower that ratio is, until you get to a one-to-one ratio and it’s no longer doing you any good as a heat pump.”

Heat pumps are fairly ubiquitous in the Lower 48, Rose says, and even in Southeast Alaska. Now people in Southcentral are discovering that they make sense for them. There’s even a homeowner in Shungnak, above the Arctic Circle, who’s using it.

“The owner says, ‘This is still worth it to me because I can use it a couple of months in the spring and a couple months in the fall when it’s not too cold yet, and in those four months I would have burned so much heating fuel that I’m paying for this device in two and a half years,’” Rose says. “In Southeast Alaska, you can use a heat pump like that year-round, and it’s a much better choice than heating oil.”

It works economically in places with lower electricity costs. In Southeast Alaska, electricity costs are low because of hydropower, but heating costs remain high because of the use of heating oil. In Shungnak, the price of electricity is subsidized through Alaska’s Power Cost Equalization program and the cost of heating oil is so high that the economics still work, Rose says.

“One of the things that we try to emphasize is that heating is the biggest part of most people’s energy budget in the state of Alaska,” he says. “And efficiency is the number one thing we should all be doing.”

Homeowners can buy more efficient appliances such as refrigerators, update old heating systems, tighten up their homes, and use LED lights.

“These things are no-brainers,” Rose says.

Another benefit of renewable energy for the homeowner is that once the system is installed, costs do not fluctuate, unlike the cost of fuel oil and natural gas, which can be volatile, Rose says. And in communities in which residents are putting excess generation back into the grid, it’s a boon for the utilities, who are receiving clean energy from systems they don’t have to operate or maintain.

“It’s a really sort of unique and exciting emerging market opportunity,” Trimble says. “Solar in the Railbelt, it’s more of a nice thing to have than a necessity in a lot of ways, but it’s really opening people’s eyes as to where their energy comes from.

“I think it speaks to the resiliency of the Last Frontier experience for Alaskans. They enjoy being able to choose where their energy comes from and like producing it themselves. It speaks to the culture of self-reliance for Alaskans.”