Friday, May 27, 2016

Forgot about that thing I use every day

That thing being hot water.

On the issue of electrifying and renewablizing uses that now come from fossil fuels, I've always focused on transportation. Until someone at my Community Choice Energy group mentioned it last week, I completely forgot home heating and water heating. Yes, we'll have to get those off of natural gas. The specific idea is that removing natural gas heating should be subsidized by electrical utilities, seeing as we don't have a carbon tax to make it happen naturally.

This won't be easy or cheap, although it is easier and cheaper for high density construction (and safer).

One significant advantage over electrifying transport is that residences stay around for a long time. Electric vehicles over their decade-or-so lifetime will benefit somewhat from a grid that's getting increasingly cleaner. Electrifying home heating is a 30-year-plus investment, and the grid even in places like West Virginia should be a lot cleaner in time, so the carbon savings will add up.


Entropic man said...

In my distant youth my parents used an electric heating system called Economy 7.

It used heaters about 4ft long, 3ft high and 1ft thick. The contained big baked clay b!ocks which were heated by of-peak electricity at night and convected the stored heat into the house during the day.

The concept may be relevant today, storing heat generated during the day from solar or wind generated electricity and releasing it for home heating at night. It would be a cheap, low tech alternative to batteries or pumped storage.

Fernando Leanme said...

Electric utilities can't subsidize anything. If you implement a program such as you propose the costs will be passed on to you, dear customer.

If you want to reduce the use of natural gas over time, it makes more sense to encourage construction of smaller dwellings. Americans live in oversized monster homes, which can be gradually reduced in size. To drive such size reductions it's useful to have very efficient mass transit, more compact urban areas, etc. it's a much smarter way to overhaul your whole system. But it will take 50 years.

Thomas Palm said...

Here in Sweden people use a lot of heat pumps. Air-air for small houses and ground-water for larger. Or you can use central heating, preferably based on waste heat from power plants or industries.

JamieB said...

You need to insulate first, then switch heating systems. But electrification (even using heat pumps) will likely need some form of heat storage or else we're going to have some almighty peaks in demand when electricity for appliances, lighting and heat is being delivered simultaneously (EVs can wait until the off peak). In the UK at least, winter heat demand is an order of magnitude greater than conventional electricity demand.

Canman said...

"Yes, we'll have to get those off of natural gas."

I'm sorry, but that is not written in stone! I think there are alternatives that need to be explored. A huge nuclear buildout (forth gen or fusion) might allow us to remove CO2 from the environment. I'd suggest freezing and storing it in Antarctica. How do we know it's not possible to have a low CO2 atmosphere and still use convenient methane for energy. There's lots of methane and maybe even prospects for new sources like clathrates. How about space tankers tapping some of those oceans of it on the moons of the large outer planets?

David B. Benson said...

Solar hot water systems make a difference in gas consumption, even in Redmond, Washington.

E. Swanson said...

One problem with solar thermal systems is that their efficiency declines as the outside temperature decreases. My home brew solar home heating system suffers a considerable decline at lower temperatures, just when I want more heat to stay warm. I knew that this would be the situation from the beginning, as I designed the collectors to be inexpensive on purpose, then over built in terms of collector area. It works well as long as the ambient temperature is above freezing, especially as the house was built with 12 inch thick walls stuffed with insulation. That's not as big a problem for the newer collectors which use evacuated tubes, but those are rather fragile, potentially suffering damage from hale storms and winds, for an example.

Another approach for hot water would be the use of PV panels wired directly into a large how water tank with a "tempering valve" on the output. With this approach, the temperature in the tank would rise much above the temperature at which a HW heater is usually set, the tempering valve mixing the hot water with cold to achieve the desired supply temperature. This setup would not need controllers, pumps, plumbing and antifreeze for the circulating water. Then too, solar hot water tanks are required to have special heat exchangers to prevent mixing of the antifreeze with the potable water in the tank, so they cost more than the usual ones. With any such system, fully retrofitting older structures can become prohibitively expensive.

Russell Seitz said...

"removing natural gas heating should be subsidized by electrical utilities, seeing as we don't have a carbon tax to make it happen naturally."

The regulation is strong in this one.

Mark said...

@ Entropic man:
My electric cooperative encourages ETS --
Electric Thermal Storage (ETS) room units are designed to use off-peak electricity for heating a specific space in member's homes (living room, family room, bedroom or basement). During off-peak hours, when electricity costs are lower, an electric coil heats high-density ceramic bricks inside the unit. The bricks store heat for at least 12 hours.