How the Lights Stay On · The Order of Operations

The Order of Operations, part 2

The remarkable thing about a heat pump is that it does not make heat. It moves heat. A traditional gas furnace burns gas to create heat, getting maybe 90 percent of the energy in the gas converted to useful heating. A heat pump moves heat that already exists, and can deliver three or four units of heat for every unit of electricity it uses. This is called the coefficient of performance, or COP. A heat pump with a COP of 3.5 is, in effect, 350 percent efficient.

For your wallet and the climate, this means a heat pump in most American climates costs less to operate than a gas furnace, and produces significantly less carbon over its lifetime — especially as the grid gets cleaner.

The installation cost depends on the size of your house and the existing ductwork. A typical heat pump installation in 2026 costs $10,000 to $20,000 before incentives, and the IRA’s tax credits and rebates can knock thousands of dollars off that price for households that qualify.

A few things to know.

Modern heat pumps work well even in cold climates. Older heat pumps lost a lot of efficiency below freezing; newer “cold-climate” heat pumps can heat a house effectively down to -15°F or lower. Maine, Minnesota, and parts of Canada are now installing them faster than warmer states. The technology is no longer a southern-states-only solution.

A heat pump can be a single unit serving the whole house, or it can be installed as “mini-splits” — wall-mounted units in individual rooms that don’t require ductwork. Mini-splits are useful for older houses where adding ductwork would be expensive.

A heat pump pulls more electricity than your old furnace blower did, because all the work that used to be done by burning gas is now being done electrically. This is why a heat pump installation may require a panel upgrade, especially in older houses with 100-amp service. We talked about that in Chapter 5.

The second-biggest energy load in a typical American home, after heating and cooling, is hot water.

A traditional water heater either burns gas to heat water in a tank, or uses electric resistance heating — which is just running electricity through a coil to make heat, the most wasteful way to use electricity for heating that has ever been invented.

A heat pump water heater uses the same principle as a regular heat pump. It pulls heat from the air around it (typically in your basement or utility room) and moves that heat into the water tank. The result is a water heater that uses about a third of the electricity of an electric resistance water heater, and that costs less to operate than most gas water heaters.

The cost is about $1,500 to $3,500 for the unit, plus a few hundred dollars to install. The IRA included generous rebates for these for low- and moderate-income households. Payback is typically five to ten years, sometimes faster.

A small caveat: a heat pump water heater takes longer to recover hot water after a big draw than a gas water heater does. If your family takes back-to-back showers in the morning, you may want a larger tank than you have now, or a slightly bigger unit. This is a manageable problem but worth knowing.

This one comes later in the list because it does not save nearly as much energy as the previous three. But it has two real benefits worth knowing.

Induction stoves are faster and more responsive than gas. They boil water in about half the time of a gas burner. They cool down the instant you turn them off. Many professional chefs now prefer them.

Gas stoves leak air pollutants into your home. Studies have found that gas stoves emit nitrogen dioxide, formaldehyde, and benzene at levels that, in some homes, exceed outdoor air quality standards. The link between gas stoves and childhood asthma is now well-established in the medical literature. The American Medical Association has called for action. Major appliance manufacturers are voluntarily reducing leak rates from new models, but the existing fleet of gas stoves in American homes — about 35 percent of all homes — is contributing to indoor air pollution every time it is used.

The case for replacing a gas stove with induction is therefore as much about your kids’ lungs as about your carbon footprint. The case is real on both counts.

But: replacing a working stove is rarely cost-effective just to electrify. The right time is when the existing stove dies, or when you are renovating the kitchen anyway. Induction units cost $1,000 to $3,000, plus possibly a 240-volt electrical run if the kitchen does not already have one.

Now, finally, we get to the visible thing.

By the time you have done steps 1 through 4, your house is using less electricity than it was before — possibly significantly less. The size of the solar system you need is smaller. The cost is lower. The payback is faster.

Everything in Chapter 9 still applies: orientation, roof age, shade, state policy (NEM 3.0 or its equivalent in your state), the local transformer, the panel inside. All of those constraints are still real.

But if your house has cleared all of those hurdles — if the roof is good, the policy is reasonable, the transformer can accept the solar — then a properly sized solar system after the other electrification is the right move. It can reduce your electric bill to nearly zero, or even produce a small credit, depending on rules.

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