Home Energy May June 2015 : Page 2
editorial Revisiting Electrification We need to stop burning natural gas if we want to meet our ultimate emissions targets. GENE ANG I must admit that I am still having trouble getting my head around this idea. But the arithmetic is fairly simple: an 80% reduc-Alan Meier sitting outside of an all-electric, zero net energy apartment complex in Davis, California. to install electric heating equipment. Worse, electrification must begin during a period of exceptionally low gas prices when heating with gas is economically attractive. We need to start talking—and acting—about it soon or else we’ll be saddled with homes served by equipment that they can’t use (or perhaps only at an unacceptable cost). People often speak of “stranded assets” like non-operational nu-clear power plants, but a gas furnace, clothes dryer, or other polluting devices can become a stranded asset, too. This is occurring with diesel cars in Paris, France. Diesel emissions have become such a problem that the mayor banned their use after 2020. Current owners of diesel cars are stuck with a stranded asset. Timing is critical to avoid backward steps in carbon emissions. If electrification begins to-day, it would be powered by dirty coal in some regions, much cleaner natural gas and nuclear in other regions, and a little renewables. That’s not the outcome we want. America’s electricity supply structure is diverse, so per-haps electrification in a region should begin only when renewables generate more than 50% of the electricity. A half renewables grid may seem far in the future, but actually it means that a few regions in North America need to start considering code changes today. How does electrification translate into prac-tical things, like outfitting a new home or the next retrofit? It means installing electric appli-ances in new homes and, in existing homes, possibly replacing gas appliances when they wear out. It does not mean the return of re-sistance heat. Instead, you will see a lot more heat pump water heaters; indeed, there will be very efficient (and quiet) heat pumps embed-ded in all sorts of devices. In the meantime, reducing the need for heat—hot water, hot air—should of course be the first goal. Insulation and hot water conservation will make the conversion more economical because smaller equipment can handle the loads. Truly sealing homes be-comes easier—and cheaper—when combus-tion is eliminated inside the building envelope. The transition to all-electric homes is going to be controversial, complicated, and expen-sive. New technologies and conservation can lower the costs but, ultimately, some difficult political decisions will determine the direction and rate of this transition. In the long run, electrification also needs to be economically attractive. And perhaps what I find difficult to wrap my head around today will become obvious in a few years. tion in carbon emissions simply can’t be achieved without drastic cutbacks in residen-tial natural gas use. In the residential sector, natural gas burned on site is responsible for about one quarter of carbon emissions. We can use carbon-free electricity generated by wind and solar to power the refrigerators, lights, TVs, and computers but that leaves the gas-fired furnaces, water heaters, stoves, and clothes dryers stick-ing out like carbon sore thumbs. We are already testing technologies for capturing and sequester-ing the river of CO 2 ema-nating from a huge gas or coal power plant, but there’s no economic technology even on the horizon to capture the trickle of CO 2 emanat-ing from a home’s furnace flue. So we need to talk about electrification. For me, electrification runs counter to every-thing I have learned (and advocated): making heat with electricity is really expensive, gas heat is more economical over the life of the device, and never select electric heat if you can avoid it. Some regions have even enshrined this philosophy into their codes, requiring build-ers to obtain special exemptions for permission YASUSHI kATO Alan Meier Senior Executive Editor 2 Home Energy | May/June 2 015
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