GTherm: Cutting Cost and Quakes From Geothermal Power
The old startup has a new way to use the Earth\'s heat to generate electricity in places where conventional geothermal technology is inadequate.
GTherm, based in Connecticut, says its innovations offer a safer, less costly alternative
Known as an enhanced geothermal system, it is even possible to convert depleted or poorly performing oil and gas wells into clean energy.
GTherm founder and CEO Michael Parrella told us in an interview that the company\'s good idea for innovation is when he realizes that they can move heat instead of water.
Three years ago, he began reading hundreds of patents related to geothermal energy and realized that most of the geothermal industry was stuck with moving water.
However, Parrella\'s knowledge of thermodynamics makes him think: why not move heat?
\"This is a Eureka moment,\" Parrella said . \".
Laser in geothermal power generation industry
Like focusing on mobile water, part of the reason is that MIT analysts released a federal-funded report in 2007 that looks at the future of engineering or enhancing geothermal systems (EGS)in the U. S.
The report found that there was hope in the geothermal system that a large amount of water was pumped through the broken rock area, and after the report came out, \"everyone stopped looking for other methods,\" said Parrella.
The MIT research, which is also landmark, also recognizes the potential seismic risks that could be caused by the use of a large amount of water to fracturing hot rocks under high pressure (
Called \"hydraulic fracturing \")
It is also pointed out that it is difficult in some areas to provide enough water for these thirsty geothermal plants.
But the concept of GTherm, called single
Well-designed geothermal systems (SWEGS) are designed to circumvent these challenges.
The SWEGS design, which has not yet been shown on a large scale, requires the creation of a \"hot nest\" consisting of a heat exchanger at the bottom of the well, a specialized hot grouting material, which Parrella calls a \"hot Highway \".
\"These are horizontal drilling, extending hundreds of feet from the well, into hot rock.
GTherm recommends using a fluid Duratherm that transmits heat rather than passing water through the rock. The fluid (
According to Parrella, \"environmental inertia\"
In a closed loop
A circulation system that passes through a hot nest to the ground.
It heats the fluid circulating through the second loop, driving the turbine connected to the generator.
As the Institute of Power Science (EPRI)
Earlier this year, it was noted that GTherm is working with GTherm and Dartmouth to analyze the SWEGS concept, which has a path to big-
Expand Business deployment.
\"In an increasingly large-scale field environment, the design, grouting and working fluid of the hole heat exchanger needs to be tested and optimized,\" EPRI wrote . \".
However, if it works as planned, GTherm\'s approach may offer several advantages over competitive geothermal technology, eliminating the need for a large amount of water and limiting exposure to corrosive minerals
The risk of earthquake is reduced, and the cost of water injection wells and production wells is avoided.
\"This is a less dangerous situation,\" Parrella said . \".
Minimum maintenance, above requirements only
Valves, pumps and generators on the ground
Or as Parrella says: \"Something that rotates on the surface of the power plant.
It takes about two acres of land per Swedish plant, but these projects do not require a monopoly on the surface of the land.
In Jamaica, for example, the company is working to develop a 10-
Megawatt power plant under the airport
\"We pick up the heat, put it on top and use it to generate electricity,\" Parella said . \".
\"The heat we extracted is equal to the refresh rate of the rock.
That means \"the well will never dry up,\" he said \".
The system can run on \"dead geothermal wells\" in deep rocks in the northeast of the United StatesS.
Abandoned oil and gas wells around the world.
However, according to EPRI, this type of single
Well systems may be most effective when deployed in highly saturated \"cracks or porous media.
The company is applying for several grants from DOE and EPRI.
EPRI has helped GTherm complete mathematical modeling, Parrella said.
Except for its America. S.
Staff, GTherm has subsidiaries in the republic of the multi-republic plus, Jamaica, Costa Rica and Chile, with a total of about 35 to 40 employees.
Parrella cites Doe\'s work estimates, stressing that GTherm\'s plants may employ more employees if they go live as planned.
There are several plants under construction in GTherm, including a 2 mw plant in the Dominican Republic;
A four-megawatt factory in southern California;
A pair of 10 MW factories in Costa Rica and Jamaica;
A 30 MW factory in Texas
According to Parrella, the cost per plant is expected to be less than $4 million per megawatt.
GTherm\'s system and Texas factory-scale projects take eight weeks to \"make a hole in the ground,\" and GTherm\'s contractors need to drill up to 36 holes.
The projects are modular because \"one nest is built every two holes drilled,\" Parrella says, and it can start generating electricity.
GTherm has been \"self\"
According to Parrella, funds have been in place so far.
Ensure that power is in the final stages of negotiations\"
But Parrella said the company is fully committed to completing these projects and added, \"We are ready for rock and roll.
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