Carbon free home heating and cooling


Berkeley, California recently banned natural gas hook-ups in new buildings. That makes Berkeley the first city in the country to pass a natural gas ban.

Cities across the West, including Seattle and San Jose, are considering similar limitations on natural gas in new buildings. Why move away from natural gas? Our article this month explores the trend and describes the preferred alternative for homeowners - energy efficient heating and cooling with electric heat pump systems. We also give a few pointers for those who want to go even farther to eliminate or offset carbon at home.


The bottom line: Extracting, transporting, storing and burning hydrocarbons like natural gas will always produce greenhouse gas emissions. By contrast, our electric grid is consistently getting cleaner, especially as more sources of renewable energy come online.

In Oregon, we have a Renewable Energy Portfolio Standard, which requires that 50% of the electricity Oregonians use come from renewable resources by 2040. Here "renewable" means that the source of power can be used repeatedly because it is replaced naturally, like wind or the sun. With a few exceptions, hydropower, which currently provides about 40% of Oregon’s electricity, does not count towards the Renewable Energy Portfolio Standard (learn more about Oregon’s Renewable Energy Portfolio Standard).

Cities and states are taking action on a large body of research, which points to electrification as one of the most cost effective ways to reduce greenhouse gas emissions (National Renewable Energy Laboratory). The strategy involves increasing the percentage of renewable energy in the electric grid while at the same time ramping up the adoption of efficient, electric technologies.

For decades, natural gas was considered among the preferred energy sources for buildings and embraced as a bridge from dirtier fossil fuels. Many people still have the perception that natural gas is cleaner than electricity, which had a larger carbon footprint back when a higher percentage of electricity generation came from burning coal.

But extracting, transporting, storing, and burning natural gas produce significant amounts of greenhouse gas emissions. Carbon dioxide comes from burning natural gas and builds up in the atmosphere because it lasts for such a long time. In 10,000 years, the atmosphere will still hold as much as 15% of the carbon dioxide emitted today. Methane, which is released during the extraction, transportation, and storage of natural gas, does not last as long in the atmosphere, but the gas is much more potent than carbon dioxide. When methane first enters the atmosphere, it traps heat at 120 times the rate of carbon dioxide.


Electric heat pumps allow homeowners to switch away from natural gas furnaces without any real drawbacks. This year alone, we installed 43% more ductless heat pumps and ducted heat pumps for homeowners in Oregon compared to last year.

Heat pumps provide both heating in the winter and cooling in the summer, while cutting energy bills by up to 50% relative to conventional systems (U.S. DOE). Like your refrigerator, a heat pump uses electricity to move heat from a cool space to a warm space, making the cool space cooler and the warm space warmer. Because it moves heat rather than generating heat, a heat pump operates very efficiently, delivering 1.5 to 3-times more heat energy to a home than the electrical energy it consumes.


Check out this feature on NPR for an introduction to heat pump technology by Vijay Modi, Professor of Mechanical Engineering at Columbia University.



The installation cost of a ducted heat pump is less than 20% more than the cost of installing a new high efficiency gas furnace and low efficiency air conditioner. Over time, you end up saving much more on your energy bills.

Installing a 96% efficient gas furnace typically ranges between $5K and $6K, with a low efficiency air conditioner adding another $4K. A new heat pump, by comparison, typically costs between $10K and $12K. Learn more about cash incentives that help to offset the cost of heat pumps in Portland and Central Oregon.

If you’d like to learn more about how much a heat pump will cost for your home, please schedule a free estimate:


Electric heating and cooling is a step in the right direction. It’s also important to acknowledge the importance of energy efficiency in other areas of your home, such as adding insulation, replacing windows, and upgrading your water heater. Here at GreenSavers, we take a whole-home perspective and are happy to provide feedback on what matters most to you. Feel free to give us a call in Portland or Bend, Oregon at 866.827.5774.

We sometimes get questions about carbon offsets. Utilities like PGE and CEC offer renewable energy programs that allow customers to offset the carbon produced by the energy they consume. When you sign up for one of these programs, you’re essentially signing up to purchase “renewable energy certificates.” Each certificate represents a given amount of electricity that’s been generated from renewable sources. When companies produce that power, they get certificates they can sell to consumers.

Prices vary for renewable energy certificates, but the average household should expect to pay a few dollars more each month. It is worth it? The World Resources Institute, the Environmental Protection Agency and the Union of Concerned Scientists have said that certificates are a legitimate way to foster the growth of the renewable energy industry.

One thing you should keep in mind is that the market for certificates is unregulated. That means the government is not keeping an eye on producers to ensure that they deliver what they promise. But there is an independent watchdog for green energy projects: Green-e. Green-e does two important things - It verifies that the energy concerned actually does come from renewable sources, and it makes sure that the certificates are not double-counted.

Summing it all up: The city of the future runs on electricity. It’s better for our environment, and less risky in the event of a major earthquake. In your home, this means making the switch to a high efficiency heat pump. Let’s build the future we want to see.

Bill Hoelzer