Global warming is a serious issue and environmentalists are trying their best to be helpful. But good intentions do not automatically translate into good policies. Proposals to eliminate the use of natural gas are a case in point.
Palo Alto Utilities provides its customers with a histogram showing natural gas use by month over a 12-month period. The peak usage typically occurs in January and February. If you take the hodgepodge of units and convert them to joules, you'll find that the energy you would use during these months by burning natural gas is about three times that used for electricity. Most of that is for heating. You can improve on that by using electric heat pumps, which are pricey but with current technology can reduce the electric power requirements by a factor of two or three. But even a factor of three still means doubling one's use of electricity.
Aside from having to substantially scale up the power grid, there is an obvious question: Where is this additional electricity going to come from? That a problem exists should be obvious: The California Public Utilities Commission would not be touting "Smart Meters" and the ability to shift usage during peak load periods if there were not capacity issues. That may work for doing the wash. It won't for heating your house.
The current breakdown of power sources, for both Palo Alto and the state, can be found at energy.ca.gov/filebrowser/download/3508. For California, the largest contributor is natural gas (34% of the total). It is a bit of a shell game because your electricity is not physically tagged with a source. Attributing it to a source (and paying that source) is intended to encourage the development of so-called clean energy.
What matters, however, is the marginal efficiency for electric power; that is, the efficiency for each additional watt produced. Utilities tend to use their most cost-efficient power plants first, with the less efficient (and typically much older) plants being used to handle peak loads, so the marginal efficiency drops as more electric power is used. Which source you attribute your electric power to is not relevant: At any point in time, if you seem to do better from an environmental standpoint, it may be at the expense of someone else doing worse because they are drawing from a less-efficient power source. The result is that switching from gas to electricity for heating is going to be less effective in reducing global warming than one would think, and in the worst case — if demand got ahead of production — it could be counterproductive. Basically, switching from natural gas to electricity can increase greenhouse gas emissions if done faster than so-called clean energy sources can be built.
The statewide breakdown is possibly the best indication of where additional power will come from, and a reasonable guess is that we would end up using more natural gas sources. As to adding more hydroelectric and wind sources, there is a lot of political opposition to putting in dams, and wind turbines, which account for about 10% of California's electricity and have to be suitably located to be effective — areas with high and persistent winds. Adding more nuclear power plants is also problematic as any proposal seems to result in the proverbial "wailing and gnashing of teeth."
Meanwhile, the data we have is not encouraging. While the best natural gas power plants are around 60% efficient, with older ones being around 42% efficient, there is an additional loss (up to 10% or so) in the power grid itself. Meanwhile, a gas furnace in a home is from 80% to 95% efficient, while the reduction of a factor of two to three in energy consumption for heat pumps does not include the losses due to power generation and distribution. This does not inspire confidence when the goal is to reduce global warming.
In addition, for single-story homes with attics in the Bay Area, there is a very simple and relatively inexpensive way to reduce the consumption of gas or electricity for heating. The attics get very hot and that heat can be pumped into the rest of the house. To avoid issues with particulates, one can use a heat exchanger similar to the Broan HRV90S. That device (under $800) includes fans, filters, a heat exchanger and four ports. By using one pair of ports for attic air and the other pair for the rest of the house (similar to the arrangement used in forced-air systems), you can heat the house, making it as warm as possible up to the maximum comfortable temperature during the day. With a well-insulated house, it will then take some time to cool back down to the point that the furnace turns on, thereby reducing natural gas use.
Finally, it seems that many people don't realize that the efficiency of a stove running on natural gas is 100% in winter if you include both cooking food and heating the house. What is classified as "wasted" energy simply warms the building, reducing the time the furnace is turned on. Regardless, cooking, drying clothes and heating water in total accounts for a small fraction of one's yearly use of energy.
We need reasonable policies, but we should not be wasting effort on things that are the equivalent of rearranging the deck chairs on the Titanic and should be careful that we do not inadvertently make the situation worse by introducing "feel good" measures that are actually counterproductive.