Electrification

This is a note about some steps that I and my family have taken to work to reduce our carbon emissions.

According to the EPA, commercial and residential use is the fourth largest source of carbon emissions overall in the U.S., generating about 12% of carbon emissions. Some sizable chunk of that is fossil fuels burned in the home for heating, for hot water, for gas dryers, and for cooking.

This matters because this use of fossil fuels is widely distributed and is controlled by homeowners. The largest source of carbon emissions, transportation, is also widely distributed, but we know how to reduce those emissions: we must switch to zero-emission cars. This is a fairly easy switch for an individual: when you must buy a new car, buy an electric car. There are many good electric cars out there, and, speaking as someone has owned one for some seven years now, electric cars are better for most uses.

The second and third largest sources of carbon emissions, electricity generation and industry, are problems that can’t be tackled by individuals, beyond general efforts like education and voting. These problems require work by the groups that run the plants. Fortunately, this work, while complex and expensive, is mostly a set of discrete large scale projects.

That is not true for home use of fossil fuels. Reducing fossil fuel use in the home requires tens of millions of individual small changes. Government can encourage these changes via the tax system, but it’s implausible for government to actually do it. Each individual home owner must make the changes themselves.

The goal is to remove any use of fossil fuel in the home. In our case, it meant no longer using natural gas. For other homes it may mean getting off oil or, occasionally, coal.

At present the only reasonable alternative is electricity. This may seem counter-productive, as electricity is also often generated by fossil fuels. Fortunately, non-carbon sources of electricity are available and are spreading fast. For example, in California, where we live, less than half of the electricity in the grid is produced by non-renewable sources. Where we live more specifically, in Berkeley, we can pay slightly extra to get only electricity from renewable sources (though of course this is something of a fiction as electrons are fungible). Also, in our case, we have solar panels.

More generally, as mentioned above, reducing carbon emissions from electricity is a set of discrete large projects. By shifting our energy use to electricity, we reduce the scale of the problem from the impossible (tens of millions changes) to the possible (there are fewer than 2500 fossil fuel electrical plants in the U.S.). It becomes possible to either replace the electricity generation with renewables, or to capture the carbon emissions at a set of locations many orders of magnitude smaller than the number of households in the country.

Moving on to what we actually did, we had three uses of natural gas: our furnace (forced hot air), our water heater, and our cooktop. As it happened, we already had an electric dryer and an electric oven.

I am strictly a software person, so the work was going to be done by other people. The first obstacle we had to overcome was explaining what we wanted. I expect that this will become easier over time. In talking to several different companies, we would explain that our goal was to stop using natural gas entirely, and they would respond with ways to reduce our overall energy use. Typical examples of this were installing better windows and improving our insulation, especially in the attic. We were also offered options like an electric water heater with natural gas for backup. We had to go back and forth with explanations of “sure, reducing energy use is great, but what we really want is to stop using natural gas.”

The second obstacle was our electrical panel. While there are many details and I don’t understand all of them, the simple view is that electrical appliances require a certain number of amps. (There are also volts and watts, but when it comes to electrifying your house they don’t actually matter.) Your house has a bunch of circuit breakers, or, in older houses, fuses, that limit the number of amps that will flow at one time. If you turn on too many appliances they will try to pull too many amps and your circuit breaker will flip. A house will have several circuit breakers, and each one is responsible for some set of lights or plugs or specific appliances. There is also a limit on how much the whole house can draw at a time, which is the size of your overall electrical service. All of these circuit breakers are there to prevent the electrical wiring from heating up too much and starting a fire.

This matters because a house that was built for fossil fuels is typically not built to have everything done by electricity. There may not be enough amps coming into the house. And the existing circuit breakers may not be large enough for the requirements of your new electrical appliances.

It turns out that getting more amps is not just a matter of swapping in a larger fuse. Upgrading electrical service is expensive. Replacing the electrical panel to get bigger or more circuit breakers is expensive. In our case we had to spend on the order of $10,000 for all the electrical improvements, though that required an additional subpanel in a different part of the house, which might not be required in every home.

The point is, if you don’t know how all of this works (I certainly didn’t), an early step in the electrification process is going to be to have an electrician come out and take a look at your system and tell you what will have to change.

The third obstacle is choice of systems. For the cooktop, this is easy: use an induction cooktop. For anything that doesn’t require actual flame, an induction cooktop works just as well as a gas cooktop. For some things, like a low simmer, an induction cooktop is actually better. Some kinds of pots and pans don’t work on an induction cooktop, but as it happened all of ours did work. You can get induction cooktops to replace any standard size gas cooktop. Since you aren’t burning gas, the air in the kitchen is cleaner. This is a straightforward change, once you’ve set up the electrical service: our new cooktop can use up to 50 amps, which is a lot.

For the furnace and hot water heater, the best choice at least in California is a heat pump system. These are two part systems: the heat pump, which goes outside, and the tank or air handler, which goes inside. The heat pump is basically a large fan, and is something like the external part of a whole house air conditioner. It is not terribly noisy, but it’s not silent. And you have to find some place to put it. One nice feature about a heat pump furnace is that you can run the heat pump backward and get air conditioning; no need for a separate unit.

You can get combined water heater/furnace systems that use a single heat pump, but for our house configuration it was simpler to get two different systems. For us each heat pump takes 20 amps, and then the air handler takes 40 amps (the water heater doesn’t need any electricity beyond the heat pump). So you can see how the amps add up pretty quickly.

Specifically our cooktop is a Gaggenau CI 292-601, our water heater is a Sanden SanCO2, and our furnace is a Carrier Performance Series heat pump and air handler. We’ve had them for over a year now, with no problems at all.

While we did all of this at about the same time, I expect that most people would do it as needed. When your water heater breaks, replace it with an electrical one. The main thing is to make sure your electrical service is ready.

Of course it’s also worth asking how much you have to pay beyond the price of installation. In our case, since we replaced the systems at about the same time, it’s an easy comparison. The year before installing them, we spent $250 per month for combined electricity and gas charges. The year after installing them, we spent $270 per month, just for electricity (with no gas charges). (These prices include charging our electric car, by the way.) So the electrical appliances are a bit more expensive, but it’s in the same ballpark.

And, of course, no more natural gas. Our local gas company, PG&E, removed our gas line entirely, cutting it off at the street, for no charge. This may make our house slightly safer in case of an earthquake: no danger of a spark from a gas leak.

If you’ve read this far, remember: check your electrical service, and the next time you have to replace any fossil fuel powered appliance, make sure to replace with an electrical one. The planet will thank you, and it’s the right thing to do.