Energy Efficiency- Does Size Matter?

Energy efficient appliances and the right mindset doesn’t necessarily make a large house energy efficient.
Published: Fri 27 Feb 2015

The US is seeing a growth in larger homes. In fact, they are now bigger than ever before, according to the country’s most recent Census Bureau data.

Normally this would sound alarm bells in the energy efficiency arena since larger homes typically consume more energy. But, apparently efficiency gains are offsetting more than 70% of the growth in that would result from the growing size and number of US households, says the US Energy Information Administration (EIA).

Geared towards energy efficiency

Energy intensity—energy used per square foot—was 37% less in 2009 than in 1980.

The EIA says that there are a number of reasons for this reduction in consumption, some of which include:

  • Energy prices

  • Increasingly efficient technologies from appliances and lighting to heating/cooling units, some of which were promoted via energy labeling programmes such as the voluntary Energy Star

  • Residential appliance standards

  • Stricter building codes-The Building Technologies Office (BTO) collaborates with the residential building industry to improve the energy efficiency of both new and existing homes. By developing, demonstrating, and deploying cost-effective solutions, BTO strives to reduce energy consumption across the residential building sector by at least 50%.

  • Incentives

  • Informational programmes

Increase in quantity and size of appliances

However, the EIA points out that the gains from energy intensity improvements would have been even larger if it were not for consumer preferences for larger homes and increased adoption of home appliances and electronics.

While the average home size has grown by about 20% over the three decade period, the increased square footage is seeing an increase in the number and size of devices such as televisions with larger screens and new or expanding end uses such as computers, networking equipment, and home entertainment devices.

So, to sum up, US households actually consumed more energy overall, 10.2 quadrillion British thermal units (quads) in 2009—up from 9.3 quads in 1980—even though they consumed less per square foot.

While energy efficiency counts for a great deal, it is important to understand that a property’s size can counteract this. It really is a balancing act which will need to be recognised by homeowners, builders and designers, as well as utilities.

Further reading

Office of Energy Efficiency & Renewable Energy – Residential Buildings Integration

US Census Bureau Data- Construction data [pdf