Heat Pumps

energy-solutionsheader image

Report on Our Ductless Minisplit Heat Pump

Testing the limits of the air-source heat pump in our new house with this cold weather

Posted on Jan 30 2014 by Alex Wilson

It’s been pretty chilly outside, if you haven’t noticed. A number of people have asked me how our air-source heat pumpHeat pump that relies on outside air as the heat source and heat sink; not as effective in cold climates as ground-source heat pumps. is making out in the cold weather. I wrote about the system last fall, well before we had moved in. Is it keeping us warm? We’ve only been living in the house for a few weeks, but here’s a quick report.


Tags: , , , , , , , , ,

Image Credits:

  1. Alex Wilson
  2. eMonitor data from Alex Wilson

energy-solutionsheader image

A Heat Pump Using Carbon Dioxide as the Refrigerant

A new generation of CO2-based heat pumps could avoid the high global warming potential of standard refrigerants and generate much higher temperatures

Posted on Aug 29 2013 by Alex Wilson

In researching and writing about building products for our publication Environmental Building News over the past twenty-plus years I’ve had an opportunity to cover some fascinating breakthrough products and technologies. One such technology I was writing about a few weeks ago is the use of carbon dioxide as a working fluid for heat pumps. 


Tags: , , , , , , ,

Image Credits:

  1. Mayekawa

Heat Pumps

energy-solutionsheader image

Choosing an Air Conditioner

How to choose between room air conditioners, central air conditioners, and heat pumps

Posted on Jul 11 2012 by Alex Wilson

[Author's note: Some modifications have been made since this blog was originally posted.]

I have never owned an air conditioner, and I don’t have any immediate plans to change that. But if I did, what would I look for?

For only occasional use and when you don’t want to spend more than $1,000, the options are limited to room air conditioners, which are most commonly installed in windows. These cool the rooms in which they are installed, though in a small house or one that’s very-well-insulated and tight, a single window unit may be able to cool much of the house.


Tags: , ,

Image Credits:

  1. Alex Wilson

green-architects-loungeheader image

Ground-Source Heat Pumps, Part 3: Five Questions

For the last part of this Green Architects' Lounge podcast episode, Phil and Chris play "Five Questions" with two professional heat pump installers

Posted on Dec 1 2010 by Christopher Briley

You are missing some Flash content that should appear here! Perhaps your browser cannot display it, or maybe it did not initialise correctly.

Download .mp3

I sent an email to Jeff Gagnon and Jim Godbout, and asked them five basic questions about ground-source heat pumpHome heating and cooling system that relies on the mass of the earth as the heat source and heat sink. Temperatures underground are relatively constant. Using a ground-source heat pump, heat from fluid circulated through an underground loop is transferred to and/or from the home through a heat exchanger. The energy performance of ground-source heat pumps is usually better than that of air-source heat pumps; ground-source heat pumps also perform better over a wider range of above-ground temperatures. installations. In this part of the Green Architects' Lounge podcast, Phil and I take some time to review and compare their answers. We also take a moment to touch on the subject of ozone-depleting refrigerants.


Tags: , , , , ,

green-architects-loungeheader image

Ground-Source Heat Pumps, Part 2: Rules of Thumb

Deciding to use a ground-source heat pump is a big step; bigger still is dealing with all of the many variables that affect the design, scale, and cost of the system

Posted on Nov 16 2010 by Christopher Briley

You are missing some Flash content that should appear here! Perhaps your browser cannot display it, or maybe it did not initialise correctly.

Download .mp3

In Part One of this episode from the Green Architects' Lounge, we only scratched the surface. Now it's time to really dig in and decide if a ground-source heat pumpHome heating and cooling system that relies on the mass of the earth as the heat source and heat sink. Temperatures underground are relatively constant. Using a ground-source heat pump, heat from fluid circulated through an underground loop is transferred to and/or from the home through a heat exchanger. The energy performance of ground-source heat pumps is usually better than that of air-source heat pumps; ground-source heat pumps also perform better over a wider range of above-ground temperatures. system is right for you, and if so, to start planning for it.

In Part Two of the podcast, we discuss:

  • A tale of two houses: Chris shares a story of two houses—one a success, and one that had to abandon using a ground-source heat pump
  • Rule of thumb for flow: 3 gal. per minute per ton of heating/cooling

  • Tags: , , , , , , , , , , , ,

    green-architects-loungeheader image

    Ground-Source Heat Pumps, Part 1: The Basics

    Feelings for this type of system run hot and cold! Love them or hate them, ground source heat pumps can offer excellent energy efficiency for your new home or renovation project.

    Posted on Oct 26 2010 by Christopher Briley

    You are missing some Flash content that should appear here! Perhaps your browser cannot display it, or maybe it did not initialise correctly.

    Download .mp3

    If you've done any amount of research on ground source heat pumps, chances are that you've heard from people who say that you'd be insane to consider them as a viable system for your house—AND you've heard from others who say you'd be insane NOT to use them.

    Where insanity and green architecture meet, you shall find Phil and me mixing a Dark and Stormy and turning on the mike to act as your good-natured guides. For this episode, we will attempt to demystify this polarizing heating and cooling system.

    In Part One of the podcast, we cover the basics and discuss:


    Tags: , , , ,

    energy-solutionsheader image

    Now’s a Good Time to Replace Your Heating System

    With the 30% tax credit in place for heating system upgrades through the end of 2010, now might be a good time to consider an upgrade.

    Posted on Apr 27 2010 by Alex Wilson

    If your heating system is old and inefficient, now is a great time to replace it with a new, high-efficiency model. There are eight months remaining to take advantage of the 30% federal tax credit that’s available for installing energy-efficient gas- or oil-fired furnaces and boilers, as well as air-source heat pumps.


    Tags: , ,

    Image Credits:

    1. York/Johnson Controls

    energy-solutionsheader image

    Ground-Source Heat Pumps (2010)

    Despite being highly efficient at turning kilowatt-hours of electricity into heat or chilled air, ground-source heat pumps have a significant drawback and usually aren't the best heating system choice.

    Posted on Feb 23 2010 by Alex Wilson

    For the past month, I’ve examined various home energy improvements for which one can earn a 30% federal tax credit. The last of these opportunities I’ll cover is ground-source heat pumps. A ground-source heat pump (GSHP) is also referred to as a “geothermal” heat pump, though I prefer the former terminology, to avoid confusion with true geothermal energyHot water or steam extracted from reservoirs beneath the Earth's surface; can be used for heat pumps, water heating, or electricity generation. The term may also mean the use of near-constant underground temperatures by ground-source heat pumps to provide heating and cooling. systems that rely on elevated temperatures deep underground from the Earth’s mantle.


    Tags: , , , ,

    Image Credits:

    1. GreenBuildingAdvisor.com

    green-building-blogheader image

    Ground-Source Heat Pumps Have Low Operating Costs

    Ground-source heat pumps are the most efficient heating and cooling systems with the lowest life-cycle cost. They are operating in all 50 states and the Canadian provinces, so there is no justification for the statement, "They don’t work here."

    Posted on Apr 6 2009 by John Geyer

    Ground source heat pumpHeating and cooling system in which specialized refrigerant fluid in a sealed system is alternately evaporated and condensed, changing its state from liquid to vapor by altering its pressure; this phase change allows heat to be transferred into or out of the house. See air-source heat pump and ground-source heat pump. (GSHP) systems collect ambient heat from the soil within 400 feet of the ground surface. This heat is concentrated by vapor-compression refrigeration units and delivered to conditioned spaces by conventional forced-air or hydronic mechanical systems. They reverse this process when in cooling mode. The technology has been used since the 1950s, so there are few unknowns. It works in nearly any climate or soil condition, and no longer needs to be proven. GSHP efficiencies are multiples of conventional HVAC(Heating, ventilation, and air conditioning). Collectively, the mechanical systems that heat, ventilate, and cool a building. equipment conversion.


    Tags: , , , , , ,

    Register for a free account and join the conversation


    Get a free account and join the conversation!
    Become a GBA PRO!

    Syndicate content