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For a college project, I'm looking to learn about direct electrical and biomass heating as a means of decarbonization of our college campus? Where can I learn about these? Searching for direct electrical heating seems to focus on subsea pipelines. Where can I learn more about them?

My college is in Rochester, NY, in the states

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There are three forms of heat transfer: conduction, convection, and radiation. Physically, there is no such thing as "direct electrical heating".

The most "direct" way to convert electricity into heat is by running a current through a resistance. The resistance will heat up. This heat can be used to heat water or another carrier for a domestic convection (free or forced)-based heating system or for radiative heaters such as heat lamps. Electricity can also power a heat pump, which might be less "direct" but more efficient.

Look up on electric heating on Wikipedia, which gives a reasonably good overview of all the forms of electric heating and provides sources for further reading.

If you want to consider how sustainable each of those alternatives is, you need to consider how the electricity is produced.

For an entirely different approach for heating a campus, consider district heating. If district heating is sourced by waste heat (for example from electrical power plants or server farms) it can be quite sustainable. Combined with improved insulation, in most climates, this waste heat can be enough to cover all heating needs. Read up on passive house for an extreme case. Biomass burning is an alternative source for reasonably sustainable district heating.

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  • An important piece of context to add -- currently in the US, commercial buildings (which includes education) use about 20 times as much fossil fuel for heating (through direct combustion on site) as electricity (source). – LShaver Apr 21 '20 at 13:06
  • You could also mention heat lamps which generate radiative heat which might be considered a more direct way of getting heat to an individual than heating up a radiator and relying on thermal conduction. – M Juckes Apr 27 '20 at 22:01
  • @MJuckes I did mention radiative heaters, I've now edited to name heat lamps as an example thereof. – gerrit Apr 28 '20 at 7:11
  • OK .. I'm sorry that I overlooked that .. thanks for the clarification. – M Juckes Apr 29 '20 at 8:02
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For a college project, I'm looking to learn about direct electrical and biomass heating as a means of decarbonization of our college campus? Where can I learn about these? Searching for direct electrical heating seems to focus on subsea pipelines. Where can I learn more about them?

Direct electrical heating probably refers to electric resistance heating. It's not the most efficient type of electrical heating available. Heat pumps win, they have a coefficient of performance of over one (COP > 1, values from 3 to 4 are typical depending on the grade of the heat source), whereas direct electrical heating has exactly COP = 1.

The benefits of direct electrical heating is that it's cheap to install and it does not require a heat source other than electricity. Heat pumps always require electricity AND a heat source such as a geothermal well.

However, a fuel-fired power plant has an efficiency of typically 30..50% depending on the type of technology (coal, biomass, liquid fuel, gas). Let us assume biomass here which should have an efficiency of around 30% typically. In direct electrical heating, 10 units of biomass create 3 units of electricity, that create 3 units of heat in electric resistance heaters.

What if you could burn the biomass directly in the building? Then you can from 10 units of biomass create perhaps 9 units of heat, the 1 remaining unit escaping with flue gases. Much more efficient.

However, what if you could use geothermal heat pumps? A geothermal heat pump has a coefficient of performance of perhaps 4, so 10 units of biomass create 3 units of electricity that create 12 units of heat from a geothermal well. The geothermal well supplies 9 units of heat and the electricity supplies the remaining 3 units.

Much more efficient that way.

However, the geothermal well needs to be drilled which is expensive. In contrast, a biomass boiler is cheaper, and resistance heaters are even cheaper than that.

And, as a hint: biomass is not sustainable. All of it is already maximally utilized today. To divert biomass to one use, it must come from some other use being reduced. Biomass is a zero-sum game. Not only that, but if we start to burn biomass en masse, faster than it grows, it will still result in a net flow of carbon dioxide to the atmosphere.

I'd focus on heat pumps therefore. They can use wind power. They can use solar power. They can use electricity produced from gas. They are very efficient, multiple times more efficient than direct electric heating.

You could also focus on the little-understood demand side too. Energy saving equals energy production. Or actually, energy saved is better than energy produced, because all energy production methods have drawbacks. If the heating energy need could be reduced by more efficient ventilation systems, better windows, perhaps more thermal insulators, reduced hot water use, reduced hot water temperature (better COP for heat pumps), etc. then harmful effects of energy creation could be reduced at the same time too.

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I don't think you should be having any problem at all researching "biomass heating" using any of the common search engines.

As for "direct electrical heating", that's an arbitrarily fine distinction, if you ask me. If the goal is de-carbonisation, then whether the electrical heating is direct or indirect is irrelevant.

As someone who has spent far too much time on both sides of the educational system, let me give you a tip: To get good grades all you need to do is reinforce the worldview of the people asking the questions — your teachers. If they think X is good and Y is bad, write a report that says X is good and Y is bad and you'll get an A. It's sad, but true.

If "direct electrical heating" is the exact phrase that a teacher has written down as a possible research topic, then — given you are having problems researching the term — you need to find out exactly what they believe that term means. "I'm having difficulty defining direct electrical heating. Could you please give me a few examples to help me get started?" is a question you could ask them that will help you understand what they think "direct electrical heating" means.

While talking to your teacher, try to work out — without asking directly — whether they think direct electrical heating is part of the solution, or isn't. The answer to this question is not as simple as you may think.

If your teacher lives or grew up in a part of Canada (for example) where 100% of the grid electricity is "cheap renewable hydro" then converting that renewable energy directly to heat could reasonably be seen as logical, sensible, and 'right'. Ditto if they grew up or lived in Australia where abundant solar is able to power micro grids. In these situations, the answer to the question — what will get you an A — is saying that yes, direct electrical heating can help de-carbonise the campus and help "save the world".

If, on the other hand, your teacher's electricity is sourced primarily from coal or gas power stations, which cause enormous amounts of obvious and undeniable environmental harm, then the answer to the question — what will get you an A — is saying that no, direct electrical heating cannot help de-carbonise the campus and help "save the world".

If you don't understand your teacher's background and biases, then you have a 50/50 chance of picking the "wrong" answer and getting a poor (or even failing) grade.

NB: Both answers are correct! [Direct] Electrical heating can help de-carbonise the planet. It can also not help de-carbonise the planet. It's all about context. The 'right' answer — which gets you the best grades — depends on the source of the electricity that powers your teacher's home — likely (but not guaranteed) to be the same as the source that powers your campus as well. You need to know what those sources are.

There are very few colleges and teachers out there that genuinely encourage independent thinking and are open to having their worldviews challenged. Very few. It is highly likely that yours don't. Clarify the question. Work out what their worldview is. Confirm and reinforce it (regardless of your personal beliefs). Get your A. Move on.

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  • I disagree with your cynical view of education and I think it distracts from the answer. – gerrit Apr 21 '20 at 12:10
  • Very few colleges and teachers are open to having their worldviews challenged. The same goes for the products of those systems. When the products of the system voluntarily police others to promote the system that conditioned them, then that is a sign that the system is working as intended. – Tim Apr 21 '20 at 12:18
  • I don't know where in the world you've had this experience, but my experience is entirely different. I went to school and university in Netherlands, Germany, and Sweden, and I found that critical, independent thinking and thinking out of the box was almost always highly valued, of course based on the best available evidence. – gerrit Apr 21 '20 at 12:22

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