Although the title may imply that this is a treatise on mid-16th century English folklore from which the common phrase evolved, relax and get comfortable for a titillating read.

This really is an explanation of building science and value engineering in construction and development. Or, “how to do it right.”

In a previous article, “You Can’t Make Pizza in a Freezer,” (read it here), I mentioned how cold is not a thing. Cold is a physiological response of your body to a set of environmental conditions.

Heat, the presence of molecular/kinetic energy, is the basis for producing physiological responses to temperature. A lot of heat feels hot. Very little heat feels cold. Again, cold is a feeling, not a thing.

Heat can be created by physical or chemical reactions.

If you burn fossil fuels, you produce heat. As well as other by-products (carbon monoxide, carbon dioxide, water, sulfur, nitrogen dioxide, nitric oxide, volatile organic compounds, hydrocarbons, and more.)

If you use electricity in a manner of resistance, you also produce heat. In this manner, you are 100% efficient.

You may think, “But I know that a gas hot water heater is more efficient than an electric resistance hot water heater, why are you telling me that the electric resistance hot water heater is 100% efficient?”

The answer relates to units of energy produced per unit of input.

We measure the input in either kilowatt hours of electricity or in therms or hundreds of cubic feet of natural gas or in gallons of liquid propane…and we measure the output in British Thermal Units (BTUs).

An electric resistance water heater converts 100% of the kilowatt hours of incoming electricity to heat the water. But…a kilowatt hour of electricity is less productive at heating a given quantity of water than if you happen to burn (combust) a certain volume of a fuel. Electric resistance converts ALL of the electricity to heat, but you still get more heat per unit of input through combustion.

We have been brainwashed to think that high efficiency, fossil-fuel burning, condensing combustion appliances such as a condensing furnace are the best of the best. Indeed, they are quite good. In fact, I have three of them at my office and two at my home. They are 96% or 97% efficient.

But we can do better:

A heat pump is a device that doesn’t burn fossil fuels to generate heat (good, we need other ways!); it merely moves heat from one location to another.

For example, consider Michigan in the winter.

I live in climate zone 5 (see image below. I live in the northernmost Michigan county that is in climate zone 5, although you can get to climate zone 7 within Michigan).

 

 

Q:  How did we derive the climate zone map?

A:  The climate zone map was created by the U.S. Department of Energy with help from good old Uncle Joe Lstiburek from Building Science Corporation. During a presentation in 2019, I remember Joe stating that he simply took note of what types of plants flourished in different geographic areas and simply compiled the data on a national level.

Q: What does the climate zone map tell us?

A: In essence it tells us that climate zone 3 is more of a cooling climate and climate zones 5 and above are more heating climates. There are building code distinctions based on climate zone for air tightness, footing depth, and more.

Back to moving heat: a typical winter temperature for my climate zone is 25 degrees Fahrenheit.

And yes, my friends in the south and in the west, that would feel cold to you.

It felt cold to me when I sat for 4 hours at a college football game on November 26th with minimal physical activity and in the wind.

Ironically, the next day when I shoveled a five cubic yard pile of dirt, I didn’t feel cold. I was sweating bullets.

(Is there a moral to this story? Yes – one’s physiological state is a composite of the external environment and what one’s body is actually doing at the time).

But, did you know that there is heat in 25 degree air?

And, further, that you can move this heat to the inside of your home?

Q:  The inside of my home is at 65 degrees. I want to heat it to 70 degrees. How in the $&$^*(&$^#^#%^&#% can 25 degree air help me??

A:  Remember, there is heat present all the way down to absolute zero, which is negative four hundred something.

Q:  So how does the heat pump really work?

A:  The coolant in the system absorbs heat from the (yes, the 25 degree) air. The coolant is compressed, which takes electrical energy, but this increases its temperature dramatically. Air is then blown across the superheated ‘coolant’ and the air heats up. Your home is heated. Done.

Q:  I’ve heard you can also cool with a heat pump.

A:  Yes, there’s a device called a reversing valve, in which the coolant can absorb heat from the indoor air, run the process in reverse, and dump the heat outside.

Q:  So, a heat pump moves heat, it doesn’t create heat?

A:  Bingo.

Now that we know how a heat pump works, consider this. A heat pump consumes electricity to move heat from one place to another. However, the effect of the heat that is moved is greater than the energy consumed to move it.

Q:  Is that called efficiency, like your 97% furnaces above?

A:  Yes…but with heat pumps, because they are ultra-efficient, we have coined a new term, called coefficient of performance (COP).

A COP of 2.7, which may be typical of a heating climate with an exterior ambient temperature of 40-50 degrees Fahrenheit, means that for every unit of energy invested in pumping heat, 2.7 units of heat are moved.

Q:  That sounds like an efficiency of greater than 100%.

A:  Yes. 270%, actually.

I have a theory. My theory is that because we are conditioned to speak in tongues, or in other words to assign and ascribe fancy technical jargon to simple and basic concepts, we never develop a working knowledge of how all the concepts fit together. I do not feel as if our society is as universally adept at understanding these concepts as it is on how to use social media. Perhaps this is a problem that begins with the technical people within a trade or discipline (the manufacturers of heat pumps or combustion appliances, for example), or perhaps this is an example of society abdicating responsibility for understanding these things.

As you think about that, let me know if you feel that my thinking is flawed. Have you previously heard the term “COP” and did you already know its meaning?

Stay tuned for next week’s article: examples of practical applications of heat pumps.
And the week after that: a deep dive into the bold claim that “Savers are Losers!”
(Which topic gets you more excited?)

Until next time,

Dr. Lee Newton

P.S. For timeless advice on how to invest profitably in real estate, download our eBook below.

References:

• https://basc.pnnl.gov/images/iecc-climate-zone-map
• https://atlas.eia.gov/datasets/eia::climate-zones-doe-building-america-program/about
• https://truenorthenergyservices.com/heat-pumps-101-faq/#:~:text=To%20provide%20heat%2C%20a%20heat,air%20over%20the%20hot%20coolant%2C
• https://home.howstuffworks.com/home-improvement/heating-and-cooling/heat-pump.htm