The U.S. Department of Energy on Friday proposed energy efficiency standards on water heaters it said would save consumers $11.4 billion on energy and water bills annually.
The standards on residential water heater efficiency, which are required by Congress, have not been updated in 13 years. Water heating is responsible for roughly 13% of both annual residential energy use and consumer utility costs, the DOE said.
These are already available and marketed as high efficiency. Costs are generally double conventional units, though there are a lot of subsidies that eliminate the price premium. The biggest drawback is both types require drainage unlike conventional models. Retrofit installations may be difficult depending on the current setup.
It’s also worth noting, heat pump models require a minimum amount of space to draw air from. I have one, and there were pages and pages in the install guide dictating the volume and clearance limitations. This makes them a no-go for say apartments where the water heater and furnace are in a small closet.
EDIT: That’s not to say we shouldn’t be striving towards this, just have to make sure the full ramifications are understood and accounted for.
They make minisplit hot water heaters, as well as water heaters that sit outside and pipe the water to an inside tank.
Economy of scales will definitely have an impact as well. It’s not like a compressor is a terribly expensive, look at how cheap basic window unit air conditioners and mini fridges have gotten. If these become the default and get subsidized even a little, they can get near enough to price parity that it’s a no brainer, a la LED light bulbs.