From Guest Blogger Bobbi Peterson: Seven Billion to One–A Single Person Can Make a Difference in Our Environment
Earth isn’t getting any bigger. A limited amount of space and resources exists for what is now a population of more than 7.4 billion human beings.
The growing number of people is not projected to slow down any time soon either. An estimated 9.7 billion people could populate the planet by 2050, and more than 11 billion may live on Earth by 2100. By then, the word “overpopulation” and its associated threats may seem like an understatement.
Consumption: The Real Threat
Many argue it’s not actually the issue of overpopulation that threatens the well-being of Earth. Rather, the real danger may lie with today’s rate of consumption – and the possibility of it getting much worse on a global scale.
People who live in wealthier areas generally leave a much bigger carbon footprint on the planet per household than those in lower-income societies, where people have historically consumed less. If that consumption trend remains the same well into the future, overpopulation may not be as big of a threat as it could be.
However, there’s also the possibility that low-income countries will eventually strive for the lifestyles of those in more affluent areas, and the higher consumption rates will follow. In that scenario, the impact of population growth could be much more dangerous.
It Only Takes One
While it may be virtually impossible to slow the growth of Earth’s human population, the world may be able to get a grip on reducing worldwide consumption rates. Its success relies on changes made at the individual household level.
Households are collectively responsible for more than 60 percent of Earth’s greenhouse gas emissions. Each household has the potential to make a positive environmental impact, and it can begin with small, simple (and often unnoticeable) lifestyle changes.
As a bonus, being environmentally conscious at home also has monetary benefits in addition to the obvious benefit of shrinking a household’s carbon footprint.
Smart Thermostat Use
Thermostat choices at home can make a huge difference. In fact, half of homeowners’ utility costs come from their heating and cooling bills. The following tips can have an immediate impact on both the environment and energy bill:
- Install a programmable thermostat to automatically adjust the temperature to suit the needs of different times of the day.
- Keep the thermostat away from heat sources to avoid having it run longer than needed.
- Use a ceiling fan to help circulate the climate-controlled air.
Further, good insulation helps get the most out of a home’s heating and cooling system. Weather-stripping, caulking and adding insulation where needed will reduce drafts and keep climate-controlled air inside.
Less Waste at Home
Sixty percent of the average American’s carbon footprint comes from the goods and services they buy and use. Recycling and reusing alone can make a difference, as every pound of manufactured product produces an average four to eight pounds of CO2.
The following simple steps can also reduce consumption at home:
- Stop junk mail through services will have direct mailers remove an address from their lists.
- Buy locally made products to avoid the impact of shipping fuel expenditures.
- Waste less food to lower the amount of methane in landfills and carbon emissions from waste transportation.
- Eat meatless meals to save at least 3,000 pounds of CO2 every year.
Updating appliances, electronics and windows will add to a home’s efficiency and reduce energy consumption.
Good Driving Habits and Car Care
People can make an impact outside of the home, too. A person’s driving habits can make up to a 30 percent difference in a vehicle’s miles per gallon. Drivers can save more than a ton of CO2 per year by:
- Accelerating slowly and smoothly and predicting stops
- Obeying the speed limit
- Maintaining a steady driving speed
- Regularly scheduling vehicle maintenance
A ton of CO2 saved annually becomes a staggering amount when multiplied by the number of years a single person drives in their lifetime. Just keeping a vehicle’s tires inflated alone can save 400 to 700 pounds of CO2 per year. The impact adds up quickly.
Future Impacts
When each household makes deliberate choices to reduce their individual consumption rates, developed societies will begin to fundamentally change their habits as a whole. At the same time, they will set an example for the rest of the world.
There is only one Earth. Living on it sustainably will leave a cleaner, safer legacy for generations to come. And with more than 7 billion people on the planet, success starts with just one.
From the article:
“Accelerating slowly and smoothly and predicting stops”
Predicting stops is good advice. Often one can even avoid the need to stop by slowing down to hit lights on green. That will definitely improve fuel efficiency. However, the advice to accelerate slowly is simplistic and often wrong.
A car doesn’t achieve its maximum efficiency until it is in the highest gear. Accelerating too slowly means spending too much time in the lower gears thereby losing efficiency.
A number of years ago, BMW did a test to determine how to drive their cars (with manual transmission) as efficiently as possible. They determined that it was best to accelerate from a stop with a heavy foot, i.e., 2/3 to 3/4 throttle, but upshift at only 2000 rpm. Unfortunately, an automatic transmission will not permit you to do that because a heavy foot will cause it to upshift at higher speeds. With an automatic transmission, it is best to accelerate at a moderate rate until the transmission shifts into its top gear and locks the torque converter. From that point, very gradual acceleration will not reduce efficiency.
When driving a car with a manual transmission, one can often significantly beat the EPA mileage. Sometimes the EPA mileage for an automatic transmission is higher than for a manual transmission. However, if a driver is really diligent about getting the highest possible mpg, in traffic he can probably do better with a manual transmission. One wonders whether it is really worth spending $1000 or more to avoid the need to shift.
Thanks for the feedback, Frank! I had no idea about the BMW test, I’ll definitely look into that some more!
Bobbie,
You may have trouble finding the BMW test since it was done in the 1960s. Of course it remains valid because the laws of physics and the basic design of engines has not changed. Now that about 95% of new American cars have automatic transmissions, finding advice on efficient driving with manual transmissions could be very difficult.
There is not total agreement on the use of air conditioning. At city speeds, using the A / C will definitely reduce gas mileage. On the highway, opening the windows increases air resistance thereby reducing gas mileage. Using the A / C and keeping the windows closed will reduce air resistance, but it is unclear whether that will increase or decrease fuel mileage. My guess is that it depends on the car, but determining the effect for a particular car could be next to impossible.
The most effective way to improve fuel efficiency is to purchase a fuel efficient car to begin with, but of course there are other considerations.
Perhaps something about engine operation and air resistance would be helpful. The power required to overcome air resistance varies with the cube of the speed. Thus, doubling the speed increases the power required to overcome air resistance by EIGHT TIMES! From Wiki:
“Note that the power needed to push an object through a fluid increases as the cube of the velocity. A car cruising on a highway at 50 mph (80 km/h) may require only 10 horsepower (7.5 kW) to overcome air drag, but that same car at 100 mph (160 km/h) requires 80 hp (60 kW).[16] With a doubling of speed the drag (force) quadruples per the formula. Exerting four times the force over a fixed distance produces four times as much work. At twice the speed the work (resulting in displacement over a fixed distance) is done twice as fast. Since power is the rate of doing work, four times the work done in half the time requires eight times the power.”
The link: https://en.wikipedia.org/wiki/Drag_(physics)
So it is easy to see why driving at high speeds reduces fuel efficiency. On the other hand, much power is wasted sucking air against the vacuum created by the throttle valve. For that reason, an engine is more efficient when the throttle is close to wide open, so the efficiency of the engine increases with car speed. However, the increasing efficiency of the engine is more than offset by the aerodynamic drag which is why fuel mileage decreases at higher speeds.
It is largely because of the pumping losses caused by the throttle valve makes a gasoline engine less efficient than a Diesel engine since Diesel engines don’t have a throttle valve. So, the a Diesel engine, there would be less penalty for accelerating extremely gradually. For an electric or hybrid car, there would be no penalty for accelerating very gradually.
This quotation from an article explains how the throttle valve affects efficiency:
“It is fairly obvious that on a gasoline engine, there are pumping losses at the throttle due to the air being forced through a turbulent restriction. The engine is more efficient at higher throttle openings as long as other factors like A/F ratio and rpm don’t get out of the efficient range. This is one of the main reasons a lower power engine is more efficient working harder than a more powerful engine hardly working.”
The link, in case you don’t mind reading a very long article with input from several people:
http://www.physicsforums.com/threads/mechanism-of-intake-pumping-losses.759971/
I know that all this may seem very complicated for someone who has not studied engines from the point of view of physics, but life can be complicated.
Anyway, I, and I’m sure many others too, appreciate the work you are doing to use energy more efficiently.