Recently my university had an alumni reunion in Palo Alto where the main speaker, an engineer who graduated a few years after me, discussed worldwide energy usage, supplies and future impacts from limited supplies and growing demand.
Worldwide energy use has been increasing by 2 percent per year for decades, while supply is falling behind, my fellow alumnus explained. Petroleum production appears to have peaked, while replacements such as solar and wind are not growing fast enough to replace lower petroleum production and meet increased demand.
He forecast a major energy shortage and much increased costs in 20-30 years. Similar predictions have been floated for some time, but so far the shortages and high prices have been transient, not permanent. What will really happen in the future? If the shortage doesn’t happen for 80-100 years, does that mean it’s not a concern? If rising energy costs and lower supplies are inevitable, how can we address the problem?
Two obvious approaches are conservation and renewable energy. How has conservation worked so far?
I found our utility bills from 1979-81 and 1996 and compared them with our 2010 usage of gas and electricity. Gas use depends greatly on weather, but I didn’t try to normalize for that. Our gas consumption was 3.45 therms/month in 1979, 3.25 therms/month in 1980, 2.45 therms/month in 1981, 1.63 therms/month in 1996 and 2.23 therms/month in 2010.
In 1981 we added insulation in the attic; in 2004 and 2010 we added insulated windows and shutters. The attic insulation has reduced gas use since 1981. Even this cold winter, we used less gas than in 1979-81.
Electric use averaged 22.26 kwh/month in 1979-81, 25.0 kwh/month in 1996 and 23.9 kwh/month in 2010. In 1979-81, we had one computer that was used occasionally each day, but since 1996, we have two computers going almost all day.
Since 1996 we've replaced almost all our lights with fluorescent bulbs but added electric heaters in several rooms where furnace heat is ineffective. Even with the added electric appliances and usage, our average kwh/month use now is only 7 percent more than 1979. Federal requirements for much higher gasoline mileage likewise will significantly reduce petroleum consumption. Conservation works.
Solar and wind energy are practical but more expensive than energy from hydroelectric or fossil fuels. Yet as petroleum supplies shrink, costs will increase, and solar and wind will become quite cost competitive. In 25 years, more than a third of all energy will probably be from solar and wind. Shortages or rationing of energy is unlikely in the next 30 or 40 years, but higher cost is probable.
We should all do more to conserve, increase energy efficiency and use renewable energy if possible.