Energy and the Environment

Every time you buy a home appliance, tune up your heating system, or replace a burned-out light bulb, you’re making a decision that affects the environment. You are probably already aware that most of our biggest environmental problems are directly associated with energy production and use: global warming, urban smog, oil spills, acid rain, and mercury deposition, to mention a few. You also probably know that driving your car less is one of the best ways to reduce your environmental impact. But you may not realize just how big a difference each of us can make by taking energy use into account in our household purchasing and maintenance decisions.

For example, did you know that every kilowatt-hour (kWh) of electricity you avoid using saves over a pound of carbon dioxide (CO2) that would otherwise be pumped into the atmosphere? If you replace a typical

1998 20-cubic-foot refrigerator with an energy-efficient 2015 model, you’ll save more than 325 kWh and ove 400 pounds of CO2 emissions per year!!

Energy Conservation and CO2 Savings

CO2 is the number one contributor to global warming, a process that scientists say could raise the Earth’s temperatures by 3–7°F over the next hundred years. Worldwide, we pump some 31.6 billion metric tons of CO2 into the atmosphere each year — about four and a half tons for every man, woman, and child on Earth. The United States is responsible for more than 17% of that, or close to 5.5 billion tons per year. On a per capita basis, that comes to more than 15 tons for each American, though some of us produce a lot more than others. Reducing CO2 emissions by a few tons per year may not seem like a lot, but the collective actions of many will have a dramatic effect.

Carbon dioxide is only one of the environmentally harmful gases resulting from energy use. Others, such as sulfur dioxide, nitrous oxide, carbon monoxide, and ozone, have much more direct effects — effects that can be seen and smelled in every major urban area of the country.

There are numerous energy-saving products and improvements around the home that can help the environment. The table Energy Efficiency and CO2 Savings in the Home shows the reductions in CO2 emissions achieved from a few energy improvements.

With some of these, you’ll notice different CO2 savings depending on the type of fuel used. That’s because some fuels give off less CO2 than others.

Reducing Your Carbon Footprint

If you are interested in reducing your carbon footprint, the table CO2 Emissions from Different Fuel Sources provides a comparison of the CO2 emissions from common household energy sources. With this information, it’s easy to calculate just how much CO2 you are introducing into the atmosphere through your energy use. Simply look at your energy bills to find out how much fuel you are using: gallons of oil, therms of natural gas, kilowatt-hours of electricity, etc. Multiply that value by the quantity of CO2 produced per unit of fuel in as indicated in the table.

You may notice that CO2 emissions per unit of energy are much higher for electricity. That difference stems from inefficiencies in the process of converting fuel to electricity and distributing the power through the grid to end-users in their homes and workplaces. Electricity often travels great distances from the power plant to the buildings where it is used. 

Despite this drawback, electricity remains vital to our way of life and our economy, and it offers a number of benefits over other fuels for many end-uses. To minimize the negative impacts, we must learn to get the most out of every kWh by using energy as efficiently as possible and looking for new opportunities to support renewable power sources and onsite or local power production.

The federal government and many state governments have recognized the importance of energy efficiency to our nation’s security and economic prosperity. Appliance efficiency standards that took effect in the early 1990s saved more than 88 billion kWh in 2000 — about 28 million tons of CO2. Updates to these standards will save more than 250 billion kWh in 2010. Despite these impressive gains, standards only eliminate the lowest-efficiency products from the market. It is up to consumers to do the rest and demand more from the marketplace. If the roughly 40 million households in climates with large heating needs boosted their furnace or boiler efficiencies to 90% or higher, some 45 million tons of CO2 emissions would be eliminated each year.

Substituting compact fluorescent lamps for the ten most frequently used incandescent lamps in every house in the country would reduce CO2 emissions by about the same amount!

To get a sense of just how effective energy conservation can be, take a look at the 1970s and 1980s. From 1973 to 1986, the U.S. gross national product grew 36% with no increase in energy use at all. Had efficiencies remained at 1973 levels, we would be spending an extra $150 billion in energy bills each year and pumping 1 1⁄2 times more CO2 into the atmosphere! We are already saving the equivalent of 13 million barrels of oil each day — half of the OPEC output — and, compared with 1973 projections, we’re getting by with 250 fewer large power plants than would have otherwise been required.