Tag Archives: Heat Pumps

Grant available to determine feasibility of large-scale geothermal energy production

From The Fairbanks Daily News-Miner, Friday, October 28, 2010:

The borough wants to know if geothermal energy can be captured in Fairbanks for large-scale power production.

A $1 million federal grant is available to help answer the question. But there’s a catch.

Whoever wins the grant must contribute a million dollars of their own.

The assembly on Thursday voted unanimously to hold a competitive process to distribute the grant.

The project must include modeling of a deep geothermal reservoir system or “hot zone” and drilling of a test well.

A successful grant recipient would also analyze and map the borehole and surface geology.

The goal is to determine whether sustainable heat flow can be maintained and whether potential exists for geothermal energy production in the borough.

School renovation is a lesson plan for Weller Elementary students

From The Fairbanks Daily News-Miner, Tuesday, October 26, 2010:

The students at Weller Elementary School initially had mixed emotions about the renewable energy project in their backyard because it caused some trees to be cleared outside their windows. But they seemed to have come around by last Thursday, when engineer Robbin Garber-Slaght gave an interactive presentation to about 100 fifth and sixth graders on the ins and outs of the ground source heat pump and solar thermal system installed in September.

“I learned that it was worth it to destroy the trees,” said fifth grader Chase Wagner. “It will help the school be green. I’m worried about the planet. It will cut down on oil and it will save money.”

Students showed their impressive knowledge of energy efficiency and power generation, as dozens of hands waved in the air to offer thoughts and ask questions in the school’s common area.

“That was a really fun group. They’re up on their science,” said Garber-Slaght of the Cold Climate Housing Research Center, which collaborated with the school district and other contractors on the experimental project.

In-ground heat pumps require some expertise

ASK A BUILDER

By CCHRC Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

Q: Recently I read the News-Miner story about the heat pump being installed at Weller Elementary School. Are there different ways to install this type of system and is this something I can do myself?

Ground source heat pumps operate in a way similar to how a refrigerator transfers heat out of an insulated box to the surrounding air of your kitchen. In this case, the heat pump absorbs heat from the ground and transfers it to a home. The heat exchange mechanism between the ground and the heat pump is typically a series of liquid-filled tubes.

There are different methods to get the heat out of the ground each of which require different installation needs.

One system is the shallow horizontal trench, which is being used at Weller Elementary.

In this configuration, the tubes are made into overlapping loops and placed approximately 10 feet in the ground. For people who live in areas of shallow ground water, it is beneficial to get the loop below the ground water table. This requires a large area, so this type of system is probably not feasible in a downtown lot, but would work well on a southsloping hillside with a lot of land available.

Another option to consider is drilling multiple wells.

These would be similar to drilling a drinking water well for a home, except that only the heat in the water is being extracted, not the groundwater itself. It is likely that more than one well would be needed to heat a house.

The third option is to sink the ground loops deep into a body of water such as a pond or lake, provided that the water body is sufficiently large to accommodate the heat demand. Contact the Alaska Department of Environmental Conservation before beginning this type of project.

All of these options are for a “closed-loop” system, where freeze-protected fluid is circulated in a closed system of piping. There are also “open-loop” systems that draw ground water directly and then inject the water back into the ground.

In most cases these are not appropriate for use in Interior Alaska.

In terms of a do-it-yourself project (and Alaskans are pretty handy) a heat pump involves digging a deep well or large trench, which will probably require hiring a driller or excavator. The equipment that makes up a heat pump is technical. Hiring someone who has been certified by the manufacturer or by the International Ground Source Heat Pump Association to install these systems is recommended.

Contact local heat pump distributors to get more information on installation.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org.You can also call the CCHRC at (907) 457-3454.

Elementary school tests heating technology novel to Interior Alaska

From The Fairbanks Daily News-Miner, Friday, September 17, 2010:

Large rolls of black tubing sat like super-sized balls of yarn next to the playground outside Weller Elementary School Wednesday. The sun shined brightly on the south-facing hillside, where a bulldozer carved out a 12-foot hole.

The balls, which are actually polyethylene ground loops, were then rolled out and buried in the ditch, where they will harvest heat from underground to use in the school during the winter. In the summer, six solar thermal panels soon to be mounted on the school will replenish heat to the earth through the same tubes. The system will not only reap savings on heat for the school district but also will test a technology that is young in Fairbanks.

“I would like to see a system that would work well in the Interior and that the public can utilize and save dollars,” said Larry Morris, projects manager for the Fairbanks North Star Borough School District.

The project is an experiment to see how well the systems work in tandem and to collect data on ground source heat pumps, which are common in the Lower 48 but rare in Fairbanks.

“What we’re trying to do here is pair that system with a solar system that will recharge the heat you take out of the ground. In warmer climates, the sun can recharge how much you take out,” said Aaron Sirois, an engineer for PDC Engineering. “We were trying to come up with a solution that’s kind of adapted to Fairbanks.”

Akutan geothermal test exceeding expectation

From APRN, Friday, August 13, 2010:

For years, the Aleutian village of Akutan has seen the energy potential in its hot springs and fumaroles. Now, it looks like that potential might be realized.

In July, work began on two exploratory wells. The first one was drilled on July 16, and it’s producing hot water at more than 360 degrees. The exploration team is drilling a second well, and they’re optimistic that the water will be similarly warm.

If it is, the exploration phase will end and the city of Akutan will start working on a power plant that would harness the steam from the ground and use it to power electrical turbines. Ray Mann is Akutan’s project manager, and he’s been working closely on the exploration project. He explains that Akutan – with its hot water at shallow depths – is particularly well suited for a renewable energy project like this.

Right now, Akutan uses diesel as its main energy source.  Mann says because the cost of energy is already high and expected to get higher in the future, a geothermal plant could help save Akutan’s residents a good deal of money.

Continue reading: Akutan geothermal test exceeding expectation

Geothermal test project near King Salmon

From The Associated Press, Friday, June 9, 2010:

The Naknek Electric Association is drilling a well near King Salmon to test the potential for geothermal energy.

Association General Manager Donna Vukich told KTUU-TV the search for renewable energy from underground heat has been a 10-year, $20 million project. If successful it could serve villages across Bristol Bay. The project requires a second test well to be drilled in September.

Naknek Electric currently relies on diesel to generate electricity.

Wash, rinse, dethaw … repeat?

Ask A Builder

By CCHRC Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

Q: I am going to dig up my foundation this summer so I can put on outside foam insulation.

Do I need to clean off my foundation in any way?

How far down should I dig? How long will the ground be frozen?

If the foundation has not been waterproofed or the product that is installed needs some touching up, then clean the area thoroughly. In the case of cement block or cast-in-place concrete, cleaning will probably involve hosing off the foundation, letting it dry, waterproofing it, then adding the insulation. For waterproofing, apply a peel-and-stick membrane or a waterproof foundation coating. Be sure to follow the application instructions carefully. These membranes work well for both new construction and retrofits, but the concrete must be clean first. If your foundation already has good waterproofing, then dig away the dirt, brush off the foundation and place the foam tight against the wall. In terms of how far down you should dig, remember that heat always goes to cold. Where you have a temperature difference inside to outside, you are going to have heat loss. The bigger the temperature difference, the more aggressively the heat will try to escape. The frostline in Fairbanks goes down roughly 4 feet on average.

Some winters, that frostline goes much deeper. Below the frostline, there is an average soil temperature of 32 to 40 degrees. A good practice is to apply rigid foam insulation that is approved for direct burial, all the way down to the footings.

Fairbanks building code requires three inches of thickness for foam below grade (below the soil).

Good resources for finding out when the ground has thawed would be the local excavation and septic companies. They work in locations throughout the area and may be able to help you predict the thawing time for your location. June is usually a good month in which to begin excavation, though if you are on the north side of a hill, in a heavily shaded area, or have wet soils, your ground may behave differently.

Q: Where can I go if I want more information on ground source heat pumps?

There is information on our website (www.cchrc.org) including heat pump resellers in Fairbanks. Also the Department of Energy has a website dedicated to energy efficiency and renewable energy (www.energysavers.

gov.) The site has general information about how heat pumps work and the considerations in installing a system. The Permafrost Technology Foundation website (www.permafrost.org) has several technical reports on the use of ground source heat pumps in permafrostladen soils. As ground source heat pumps grow in popularity, we are seeing more being built in the Fairbanks area. CCHRC is beginning research projects that will look at the effectiveness of ground source heat pumps in our region and should have some preliminary information on our website by next spring.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org.You can also call the CCHRC at (907) 457-3454.

A heat pump, for what it’s worth

ASK A BUILDER

By CCHRC Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy, and the many other parts of home life.

Q: What is a heat pump and can it work in Fairbanks?

A heat pump is a mechanical system that uses a series of liquidfilled pipes or tubes run underground to heat (or cool) a building. The liquid captures the ground heat and uses it to heat your home. You might think our Fairbanks ground would be too cold to support such a system, but even at lower temperatures a heat pump can still function appropriately. In Alaska, this tubing has antifreeze added.

In Fairbanks, these tubes need to be buried below the frostline (about 10 to 12 feet down) where the temperatures are fairly stable across the seasons. Heat pumps use more electricity than the typical house, but the increased costs are offset by the savings in fuel. There is some concern that, depending on your site, the heat pump will take enough heat from the ground to cause freezing, however more research needs to be done on this question. Locally, we’ll probably see more of these systems being installed in the next few years, but for now, it is an emerging technology for our area.

Q: My boiler needs to be cleaned. Is that something I can do myself, or should I call a professional?

You can do it yourself but it is a messy and sometimes difficult job. Older boilers may require removing side shields, top pieces, gaskets or other parts that can be damaged and cause leakage.

Most newer boilers have hinges and open from the front, making them much easier to clean. These boilers make it simple to get a brush onto the heat exchange surfaces and leave few places to gather soot. In the long run, it is probably best to have a professional do the cleaning.

Q: If I want to build a higher tech home and add some solar panels or wind power, how does orientation play into that?

Fairbanks is a tough place for wind power because it is generally a calm region of the state. The orientation of your home will not be a hindrance to adding any type of wind system as long as you have the wind resource. High areas in the hills around Fairbanks have the best potential for this kind of renewable energy system. Fairbanks is certainly a good place for solar much of the year. Solar systems should be oriented to the south in order to catch as much light as possible.

If you are building a new home, orienting it as much as possible toward the south will be advantageous for any kind of solar energy collection, whether passive or panels.

If you want to add solar panels on to your house, place them on your roof or outside walls at the height they will collect the most light.

Before making any decisions it is best to contact a solar installation company that can do an assessment of your property. These companies can do an analysis that will tell you where panels will receive the most sun exposure year round.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at mailto:akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.

Residential Geothermal Power Reality, Not Science Fiction

BY Adam Wasch, Energy Outreach Consultant for CCHRC and UAF CES
Energy Focus: Fairbanks Daily News-Miner April 23rd, 2009, Section A3

“Was I to believe him in earnest in his intention to penetrate to the centre of this massive globe? Had I been listening to the mad speculations of a lunatic, or to the scientific conclusions of a lofty genius?”

These lines are from the campy adventure novel, “Journey to the Center of the Earth” by Jules Verne. Science is cool, but science fiction is cooler. Writers apprehend the future in their fantasies, often articulating what scientists later invent. Though writing in the 19th Century, Verne appears to have anticipated modern-day air conditioning, submarines, and television. Continue reading →

Stimulus money for homeowners

From treehugger.com on February 20, 2009, retrieved on 3/6/09:

The stimulus bill has finally been passed and signed into law—and now it’s time to help put the thing into action. Which shouldn’t be tough to do: tucked into the thousands of pages of confounding language, there are tons of fantastic new tax credits you can get simply for buying great green stuff. Here’s what our government’s blowout sale’s got in the catalog.

Click here to see the list.