There are two types of energy consumed by an appliance.
- The one that we're most familiar with is the energy used while the appliance is in operation (or in case of vampire power, while it is plugged in).
- The other type -- and what you're inquiring about -- is known as embodied energy: the energy required by the other phases of an appliance's life cycle. As you astutely point out, it takes energy to manufacture an appliance, (as well to acquire the raw materials), transport it to factories, warehouses, stores and homes, and then to dispose of it via recycling or landfill.
Energy consumption is greatest during use phase
As far as I am aware, Energy Star looks only at energy consumed by the use of an appliance and does not consider embodied energy. With some types of products, that would be a serious limitation. Appliances, though, tend to last a fairly long time and the vast majority of appliances' energy consumption occurs during that usage phase. One way to think of it: the appliance is manufactured (and disposed of) once, but used many, many times.
That said, I suspect you are right that appliances are not as durable as they once were, probably due to their increasing complexity and reliance on electronic components. I dread the day when the controller on my range goes all HAL on me (what do you think you're cooking, Dave?) because repairing it will cost nearly as much as getting a new range.
Durability can be a problem
We've looked before at the question ofwhether it is greener to replace or reuse an appliance.Oddly enough, appliance durability can actually be a problem for energy conservation.
- Refrigerators, for example, tend to last forever (unless, of course, it's a holiday weekend and your fridge has suddenly decided to abandon you in your time of need, leaving you with a rapidly spoiling feast for twelve).
- That means it takes a long time for more energy-efficient models to replace the old hogs that keep churning away.
My 15-year old fridge, dishwasher and washing machine all have newer, much more efficient cousins, but it probably doesn't make economic sense to replace them. Energy Star recommends that refrigerators older than ten be replaced, but I ran the numbers on mine, using the wattage of my nearly ancestral model versus an Energy Star-rated new one and factored in my utility company's rates. I'm going to have to keep my old one at least a few more years.
That calculation, though, only takes my direct costs into account; it doesn't factor in "external" environmental costs or social costs.
- From a societal point of view, replacement with energy- and water-efficient models would likely be a good proposition.
- With or without those societal costs, however, the impact of embodied energy is still relatively small in a product that consumes energy while in use.
If the embodied energy of my fridge were added into the equation, it would probably extend the replacement date out further, but only by a little.