As the cost of fossil fuel climbs, interest is growing in geothermal systems, which take heat stored beneath the Earth's surface and moves it above to furnace units and distribution systems inside buildings.
Tapping the Earth's energy is a hot topic and getting hotter as the cost of fossil fuels rises. "It's the best thing we ever did," says Pat Dobben of Drayton, Ont., as she describes the geothermal system she and her husband, Luke, installed in their 120-year-old farmhouse three years ago. At that time, she says, only a quarter of the 1,900-square-foot house was insulated.
"The rest was double brick. That was how they did insulation years ago. With the oil furnace, our bills were atrocious - over $4,000 a year - and the house was still cold."
They decided to bite the bullet and invest $20,000 in a water-based geothermal system. "Now, I have a warm house in winter and a cool house in the summertime," says Dobben, "and we don't have much of a hydro bill."
According to NextEnergy Geothermal, the company that installed the system, "the Dobbens are saving approximately 65 per cent annually on their heating bill and, with the additional savings on air conditioning and hot- water bills, can expect a full return on their investment in eight years - at current oil prices. The Dobbens were also eligible for a federal grant for installing a geothermal system."
A geothermal system takes heat stored beneath the Earth's surface and moves it from underground pipes to a furnace unit and distribution system inside a building, where it is dispersed evenly.
To cool, the system works in reverse, returning heat to the soil.
Greg Jarvis, a retired vice-admiral living and working in Ottawa, has "spent the better part of 10 years planning and designing" the home where he and his wife, Rita, will live after retirement. "We're in the process of building right now and hope to be in it by the time the snow flies," he says. "We heated it all last year. The whole idea is to have the most energy-efficient home possible " - which is why he decided on a geothermal system for the 3,000-square-foot bungalow in Ashton, Ont.
"There is no better form of heating and cooling a house. I have a direct-expansion system, which means that, in my basement next to the furnace, are six pipes that go 100 feet down into the ground at 15-degree angles," he says. "The static water level here is 35 feet, so I have 65 feet immersed in water - the best medium of heat exchange." "A lot of thought went into the design," he adds, and a back-up generator is in place for emergencies. "I'm very proud of the house and quite confident we could survive anything here."
The new $39-million library at Vancouver's Langara College, which has earned several awards for its environmentally friendly design and its architecture, has a geothermal grid. In addition, it uses radiant heating and cooling and wind-driven natural ventilation.
"When we were designing the library/classroom building, we wanted it to be energy efficient, and we have a direction from the college board to do whatever we can to help in the reduction of greenhouse gas emission," says Jay Strachan, Langara's director of facilities and purchasing.
He says the LEED (Leadership in Energy and Environmental Design) program, with gold, silver and bronze levels, became more prominent as construction was about to begin.
"So we decided to go for gold," he says. "Of course, it takes much longer for us to get a payoff in this part of Canada because of the mild climate, but we felt an educational institution should lead the way in this form of heating and cooling."
Where private homes are concerned, John Lobb, vice-president of Geologic Heating Systems in Carp, Ont., says federal financial support is greater for retrofits than for new buildings.
"You get only one small rebate if you put a geothermal system into a new home. You get more help in grants with a retrofit," he says, noting that for a successful installation, the house must have the appropriate duct capacity. "Every home is an individual case."
The choice between a water-based and a waterless, dry-expansion geothermal system also depends on specific situations, he emphasizes, noting that, while one system might be more appropriate than the other in a particular location, one is not intrinsically better than the other. "In vertical installations, the dry-expansion systems are usually a little cheaper to put in because a waterless system requires less depth in the bore hole per unit of heat. But waterless systems are not covered by the ecoEnergy grant. We work out the bottom line, comparing performance and considering rebates, when we make our recommendation to the client."
The installation of either type of geothermal system, which averages around $14,000 to $17,000 more than a conventional system, will reduce utility costs sharply, Lobb says.
"In new homes, the payback is typically five years, depending on the source of heat. But the time is getting shorter as the price of fossil fuels goes up. It's also worth pointing out that fossil fuel prices, especially oil, are dictated by world markets - even natural gas prices went up by 44 per cent in July - whereas the relatively small amount of electricity you need for a geothermal system is supplied by provincially regulated utilities. So there's a political will and the capability to keep electricity prices from skyrocketing."
Regaining the cost of installation on retrofits is more variable as the costs, grant and rebate eligibility also vary, but is typically between five and seven years.
Geothermal heating is the answer to rising fuel costs, says Glenn Kaye, president of Maritime Geothermal Ltd. in Petitcodiac, N.B., a company that has manufactured heat pumps for more than two decades. "Our team firmly believes that renewable geothermal heating and cooling is the natural solution to rising energy costs and the global warming crisis."
via The Gazette