Energy Efficiency: The Big Picture

The superiority of natural gas translates directly into customer savings. Numbers can be deceptive. Energy efficiency ratings for home appliances, for instance, make it seem like electric appliances are more efficient than natural gas. But nothing could be further from the truth. When overall efficiency is considered alongside the cost to the consumer, natural gas wins hands down.

“Evaluating energy use based on equipment efficiencies does not allow us to see the entire picture as it takes approximately three times as much energy in the electrical generation process to create one unit of usable energy than it does for natural gas,” said Michael Noll, an architect from Boston who is also the founder of, which provides technical tools for architects as well as advice on home efficiency and sustainability.

To understand why natural gas almost always comes out on top in terms of overall efficiency and low prices for the consumer, Noll outlined a couple of key factors.

Site energy

Site energy is the amount of energy consumed in the home. Measures of site energy are based on the overall amount of energy converted to useful power.

Source energy

Source energy considers the entire chain of energy production from creation to distribution and energy usage by the consumer.

To achieve a fair comparison between electricity and natural gas, a figure known as site-to-source ratio signifies the amount of energy used compared to the amount of energy consumed to create that power.

According to Noll, energy purchased from the electrical grid has a site-to-source ratio of around 3.14, i.e., it requires 3.14 units of energy to deliver one unit of energy to the site.

“Much of this discrepancy is due to losses on transmission,” said Noll. “In contrast, natural gas provides a site-to-source ratio of 1.05.”

When source energy is considered, more than 90 percent of the natural gas that enters the pipeline reaches you, compared to only 30 percent for electricity, according to the Environmental Protection Agency. Natural gas is far superior in terms of cost and overall efficiency while being better for the environment.

So when evaluating natural gas appliances against other fuel and power sources, it makes sense to use source energy. The superiority of natural gas translates directly into customer savings.

According to a study by research firm IHS Cambridge Energy Research Associates, switching from an electric to a natural gas-heated home saves U.S. consumers more than $5,700 on average over 15 years, and households with natural gas heating, cooking and clothes drying spend an average of $654 less annually.

This article, written by Drew Robb, and others surrounding the theme Natural Gas: Taking Care of Our Planet can be found in our Spring/Summer edition of Natural Living.