Where’s the “Geothermal Revolution” (or even the GSHP Revolution)?

CBC has recently reported on a proposed community-scale ground source heat pump installation, including sceptical comments from me.

My scepticism arises from seeing many district heating proposals like this come and go. Hears are two examples from heating markets with very costly conventional alternatives, one in Yellowknife and another in Whitehorse

I am also concerned seeing many individual-site geothermal installations fail in Ontario. Typical problems include the ineffectiveness of the systems to supply sufficient heat on the coldest days, fast depreciation, and rising power costs.

The CBC story accurately quotes me hoping that the developers can prove me wrong. One comment I made to CBC that didn’t make the story (understandably given their story length) was to remark on benefits of the proposal, including much better sound performance in aircon season.

If the Markham project is going to work, the developers will need very smart engineering and finance.

The title of this post draws on Ontario’s former environment minister Glenn Murray, who back in 2011 promising a “geothermal revolution”. (See minute: 10:30 from this https://www.youtube.com/watch?v=b59ugwetaOg&feature=youtu.be. I suggest that history has proven all of Glenn Murray’s major energy ideas expressed as a government minister to be pretty thoroughly debunked at this stage.

Here is me debating another reliable guide to unreliable energy ideas, Tom Rand, on the topic of geothermal back in 2011. Unfortunately, the links are now stale and I can’t find working links.

Here is blogger and design editor at treehugger.com, Lloyd Alter, arguing both that I understand nothing about the topic in question and also that “many in the green building world have given up on GSHPs”.

In response to the CBC coverage, I have received a couple of private complaints from GSHP developers. I want to express a particular invitation to my detractors to comment here. On this site, I invite any and all (civil) comments and criticisms. It would be particularly useful to my readers (and me too) to see documentation on successful GSHP installations.

Postscript November 21

In an exchange on Twitter, Tom Rand made the following remark:
One problem we tried to solve in the geo company I invested in was to professionalize design & installation (including drilling) to overcome what was essentially a mom-and-pop industry. We didn’t succeed (as they have in Sweden.). @mattamyhomes will have better success, I think.

Geothermal and GSHP technologies have failed to deliver much of a dent in the Canadian heating market despite massive flows of subsidies over a period of decades. Examples include the Ontario Green Fund, the federal ecoENERGY Retrofit, federal and provincial Home Renovation Tax Credits, and many other government sources.

Here is an article from “Corporate Knights” magazine from November 2008 wherein Rand promotes his geo heating company, CED. Among his claims from 2008: “Market conditions are just right for geo to reach what Malcolm Gladwell calls the ‘tipping point’. The economics work.” Ten years later, there is no market evidence for this claim.


  1. Tom A’s quote in the CBC article mentioning suitability for Iceland & California and the blog post linking to Yellowknife and Whitehorse are all locations where the Earth’s mantle is close enough to produce high temperatures to heat water directly. Like hot springs.

    Those deep-Earth-geothermal projects are indeed rare due to required conditions. The Mattamy-Enwave project is a regular heat pump project with a different ownership model. It is unfortunate that both very different technologies share the same name.

    So let’s just look at heat pump systems. The ground source heat pump sector for homes and buildings has many examples of problems. To do it well requires professional expertise. But it does work. There is even a CSA standard for GSHP systems.

    With advances in heat pump technology however, the condensing side no longer needs the moderate temperature of a ground or lake heat exchanger and can work in air down to -25 C. Eliminating the ground or lake loop greatly reduces capital cost.

    I expect the Mattamy-Enwave project will work just fine, but home purchasers should not expect to have lower heating/cooling bills. It is however much lower in GHG emissions.

  2. You’re wrong on this.

    Ground source heatpumps are very effective. They maintain full capacity and efficiency regardless of how cold it gets outside. They’re far more forgiving than air source heatpumps. They typically supply 3 to 5 kw of heat for every kw consumed.

    The technology is not really “geothermal” -> it has nothing to do with tapping hot springs, etc.

    Like any other type of heating system, it has to be properly designed (both the ground loop and duct system), installed and commissioned.

    The problems come when a contractor that’s used to slapping in grossly oversized, improperly set up furnaces starts putting in heatpumps, whether ground source of air source.

    Gas furnaces are very forgiving in the short run -> even on a poorly designed duct system, they will still keep the house warm. They tend to be grossly oversized, especially in older homes. It’s not uncommon to find a 75 000 btu output furnace in a house with a 30 to 50 000 btu/hr heat loss.

    The capacity for gshp is much lower than that of a typical furnace and the airflow requirements relative to heat supplied can be double. The duct system has to be designed accordingly and the unit sized for heating, not cooling to avoid the use of supplemental resistance heaters. The typical new, well insulated ontario house with a 40 000 btu/hr maximum heat loss may only need a 45 to 50000 btu/hr high efficiency furnace and 2 ton a/c, both of which need around 800 cfm of airflow.

    This same house would need a 3.5 to 4 ton ground source heatpump, requiring 1400 to 1600 cfm of airflow. Ideally, would need to use a 2-speed heatpump which runs on low for cooling to properly dehumidify in the summer. Much larger ducts.

    You stick a 2 ton system in and it won’t have a chance in hell of supplying sufficient heat.

    The only real issue is economic. If the electricity is expensive and the new new type of power plant being built is natural gas, as in ontario, it makes more sense to just install a regular furnace. No real savings due to the huge cost difference between electricity and natural gas. Now if the electricity is mostly generated by hydro dams and is affordable, like it is in quebec and manitoba, the technology is worth while.

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