It makes sense to “lightweight” automobiles, even though it costs more to use premium materials such as aluminum or magnesium than to use steel. The general rule of thumb in the auto industry is that you save about seven percent fuel economy for every 10 percent vehicle weight that you reduce. Reducing vehicle weight impacts almost every other attribute in a positive manner:
- it burns less fuel,
- lowers emissions into the atmosphere,
- accelerates and brakes better,
- provides less “wear and tear” on load bearing parts in the suspension and brake systems and,
- is more nimble in handling.
The aluminum alloys in the automobile industry perform equal or better to steel in dent resistance. Finally, pound for pound, aluminum absorbs twice the crash energy as steel, helping the all-aluminum Audi A8 achieve 5-star crash performance levels.
Despite this, mainstream automakers continue to address fuel economy issues by improving powertrains, shrinking vehicle size, or a host of other band-aid fixes. A lighter weight vehicle is more efficient (efficiency improvement per unit cost) than most of these other approaches and it improves the performance of these other approaches in the process!
Traditionally, it was high price tag vehicles (Audi, Ferrari, etc.) that were made from lightweight materials. Later this year, the 2015 Ford F-150 will launch with an all-aluminum body structure. The F-150 is one of the highest production volume vehicles in the world, so this is a game changer not just for Ford, but for the global auto industry. For the above-cited performance reasons, Ford wants you to equate an aluminum F-150 with other aluminum vehicles like the Space Shuttle or the battle-tested Army Humvee, not a soda can.
So what does this have to do with insulation? We often hear homeowners being urged to switch to more efficient light bulbs, windows, doors, appliances, etc. to address utility bills. Yet millions of homes are under insulated.
Like vehicle weight, insulation in a house is not very visible or exciting – at least not in the same way that a new stainless steel Energy Star refrigerator might be. Yet, like vehicle weight, improving insulation in a house is one of the smartest things you can do to lower your operating costs. Adding insulation helps improve the performance of things like high-efficiency HVAC equipment/systems, new appliances, or windows that are touted for their energy saving potential.
We should all learn a lesson from the auto industry: it may not be as cool as an 8 speed transmission (new windows), but reducing vehicle weight (adding home insulation) is the smart move to make before you invest in other energy savers.