Energy Use in Products and Services: Overview & Tips

Jan 12, 2012 | Energy Efficiency

Energy is used to make the many, many items that surround us in our homes, offices and stores.  Read on for more information on this important topic.

THE BIG PICTURE

We are a nation of consumers, and it shows up in our energy use too.  Products and services  -  the things we buy that are not food, driving or flying  -  add up to more than 50% of the nation's energy use.  There are always differences in energy accounting systems, and personal lifestyles, but for many people, products and services can be as much 70% of their energy footprint.

Look around the room you're in. Each object took energy to make and transport. This is known as "embodied energy."  Services - such as banking, insurance, and entertainment - typically have a small fraction of the embodied energy of products.

It's hard to track all this energy use down to the product level, but reliable data is available at the category level. So the data show that cars have more embodied energy than socks, but the data are not available to say that socks from Company A have less embodied energy than socks from Company B.  Because of that lack of detailed data, it is not possible to discriminate between products.  Consequently, energy saving recommendations for products and services must be very general.

SURPRISING FACTS

#1 Products and Services = Commercial and Industrial.

Often data on carbon emissions and energy use is presented in terms of residential, commercial, and industrial sectors.  This gives the appearance that individuals consume energy only in the residential sector. But, in fact, we buy our products and services in commercial establishments (shops, malls, or even online stores), and our products are made in the industrial sector. The commercial and industrial sectors use the majority of our country's energy.

#2 Only 10% of the lifetime energy use of a car is embodied energy.

Several detailed studies have been made of energy use and CO2e emissions in auto manufacturing. The bottom line is that 90% of the lifetime energy use of a car comes from the gasoline used in driving. The car's efficiency (mpg) and miles driven each year are the two largest factors determining lifetime energy use.

#3 Reuse saves enormous energy.

Studies show that purchasing item that already exists uses 5 to 15% of the energy embodied in the purchase of a new item.  No matter how much we recycle, reuse will always have the highest energy savings.

ENERGY SAVING TIPS

Reuse Items.  Consider buying used items instead of new.  For most products, the energy used in manufacturing is 7 to 10 times larger than the energy used in transport.  So to save energy, buy used, even if you have to ship it.

Recycle! It's a familiar call to action, but it works.  Recycling can save energy.  For example, recycled aluminum needs only 5% of new aluminum when making cans.  Not everything can be recycled, but every bit helps.

If thinking about carbon savings, avoid livestock-based products.  Animals emit greenhouse gases, so products from livestock-based products are particularly high in CO2e emissions.  For example, if choosing between leather shoes and non-leather shoes, it is likely that the leather shoes will be associated with much higher CO2e. The energy difference between the two pairs of shoes won't be nearly as large.

FOR MORE INFORMATION

See the WattzOn white paper on energy use in products and services. To dig deeper, take a look at the many studies at the Green Design Institute at Carnegie Mellon University.

Keywords: Energy savings; energy content of autos; livestock emissions; energy saved from recycling.