Mr. Electricity is your guide to saving energy in your home.
Rebates & Tax Credits
for U.S. consumers
Rebates. For buying energy-efficient appliances like refrigerators, washing machines, and air conditioners.
Tax Credits. For installing things like high-efficiency water heaters, air conditioners, heaters, roofing, insulation, doors & windows, solar panels, etc.
We're recommended by the government of Berks County, PA.
Related sites:
Watt Watt. News about efficiency and conservation, written by readers of the site.
Home Power Magazine. All about renewable energy for the home.
No-Impact Man. Blog about a family striving to have no net impact. (i.e., What little they use, they offset.) Inspirational.
Off-Grid. News and resources about living without being connected to a utility company.
Ask Mr. Electricity in the news:
Cold, hard cash, Kansas City Star, June
22, 10
Stretch your dollar, not your budget, Globe
and Mail, May 18, 10
Energy-saving schemes yield ¤5.8m in savings, Times
of Malta, Dec. 20, 09
Four ways to reduce your PC's carbon footprint, CNET,
Dec 2, 09
Enjoy the mild weather, low electricity bills, Detroit
Free Press, Jul 18, 09
The most energy-efficient way to heat a cup of water,
Christian Science Monitor, Jun 16, 09
Ten ways to save energy, Times of Malta,
Jan 3, 09
Measuring your green IT baseline, InfoWorld,
Sep 4, 08
The Power Hungry Digital Lifestyle
(PDF), PC Magazine, Sep 4, 07
Net
Interest, Newsweek, Feb 12, 07
Going Green, Monsters and Critics, Jan 6,
2007
A hunt for energy hogs, Wall Street Journal
Online, Dec 18 06
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If you like this site, you might also like some of my other
sites:
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Carbon
footprint calculator
We all know that certain choices use energy and cause
pollution, but how do those things stack up against each other? For
example, how does the pollution savings from ditching your car compare
to the savings from going vegetarian? And how does the energy you save
in your home compare to the energy you save by not taking a certain
airline flight?
I wanted to know, and I found the other online calculators lacking in
important ways, so I spent a solid week researching the
data and creating the calculator below. Following the calculator are
all my detailed calculations and sources. So give the calculator a
whirl and see how you stack up!
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Electricity matters because most electricity in
the U.S. is generated by burning coal. Coal-burning causes
tremendous pollution, and is a powerful contributor to global warming.
As a result, the coal industry has been touting what they call "Clean
Coal", which is little more than a marketing ploy. There is no such thing as clean coal.
You'll also note from the calculator that your
house has a bigger effect on the climate than your car! That's why
I put home energy first in the calculator.
Electricity used in different parts of the country
creates different amounts of pollution, because some places get a
larger share of their electricity from coal. But this calculator keeps
things simple by using U.S. averages for pollution caused by
electricity.
You'll get the most accurate answer by entering in
the number of kWh you use (which you can find on your electric bill)
rather than cost per month, since the cost of electricity in the U.S.
varies widely from one area to another (7¢ to 30¢ per kWh as I write
this). If you enter $/mo. then I first subtract $10 to estimate the
fixed cost that the utility charges you each month for the privilege of
being their customer, and then figure the rest was for energy at
11¢/kWh, the national average.
The average U.S. household uses 920 kWh per
year of electricity. I assume that single-person households use
half that. (There are 2.67 people per household, but I don't divide by
2.67 because I want to account for the fact that multi-person
households are more efficient. If I divide average household use by
2.67 then I'll understate the individual's use. For example, both a
3-person household and a 1-person household will each have one
refrigerator, so the fridge in the 1-person house uses more energy per
person.)
On a separate page I have complete sources, references, and calculations.
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You can enter your gas usage either as the
amount you pay per month, or the number of therms you use per month
(which you can get from your bill). If you enter the cost, then I
first subtract $10 as an estimate of the fixed cost your gas company
charges you no matter what, then figure that the rest was charged at
$1.50/therm.
If you know your fixed monthly charge is higher or
lower than $10, you can account for that to get a better estimate from
the calculator. For example, let's say you enter in $14. The calculator
subtracts $10 and figures you bought $4 worth of gas. But say the gas
company charges you only $8/mo. to be a customer. In that case you
really used $6 worth of gas ($14 - 8). So to get the calculator to
figure you bought $6 worth of gas, enter in $16, and it will subtract
$10, leaving $6.
Only 64 million of the nation's 107 million
households use natural gas. Of those using gas, they use 688 therms per
year on average, or 57.3 therms per month. To come up with the default
figure for single-person households, I assume they use half of what a
typical household uses. (There are 2.67 people per household, but I
don't divide by 2.67 because I want to account for the fact that
multi-person households are more efficient. If I divide average
household use by 2.67 then I'll understate the individual's use. For
example, both a 3-person household and a 1-person household will each
have one hot water heater, but the water heater likely won't use 3x as
much energy in the 3-person household, so the heater in the 1-person
household uses a little more energy per person.)
To figure the tons of carbon from the average
household and the average person for the right-hand column, I divide
the total amount of carbon generated by natural gas by the total number
of households (107 million) and the total number of people in the U.S.
(300 million), respectively.
On a separate page I have complete sources, references, and calculations.
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You can enter your heating oil usage either as
the amount you pay per month, or the number of gallons you use per
month (which you can get from your bill). If you enter the cost,
then I first subtract $10 as an estimate of the fixed cost your oil
company charges you no matter what, then figure that the rest was
charged at $4.00/gallon.
If you know your fixed monthly charge is higher or
lower than $10, you can account for that to get a better estimate from
the calculator. For example, let's say you enter in $14. The calculator
subtracts $10 and figures you bought $4 worth of oil. But say the oil
company charges you only $8/mo. to be a customer. In that case you
really used $6 worth of oil ($14 - 8). So to get the calculator to
figure you bought $6 worth of oil, enter in $16, and it will subtract
$10, leaving $6.
Only 8.1 million of the nation's 107 million
households use fuel oil. Of those using oil, they use 889 gallons per
year on average, or 74 gallons per month. To come up with the default
figure for single-person households, I assume they use half of what a
typical household uses. (There are 2.67 people per household, but I
don't divide by 2.67 because I want to account for the fact that
multi-person households are more efficient. If I divide average
household use by 2.67 then I'll understate the individual's use. For
example, both a 3-person household and a 1-person household have a
furnace, but the furnace likely won't use 3x as much energy in the
3-person household, so the heater in the 1-person household uses a
little more energy per person.)
To figure the tons of carbon from the average
household and the average person for the right-hand column, I divide
the total amount of carbon generated by fuel oil by the total number of
households (107 million) and the total number of people in the U.S.
(300 million), respectively.
On a separate page I have complete sources, references, and calculations.
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As you can see from the calculator, the average
home pollutes more than the average car.
The EPA reports the average fuel economy of the
U.S. fleet as 22.2 mpg, but actual fuel economy is only 20.36, as
listed in the sources section. Therefore, for
whatever MPG you enter, the calculator assumes your car gets only 91.7%
of that.
There are 107 million households in the U.S. but
only 99 million have a car. Of those with a car, they use 1,141 gallons
of gas per year on average, or 95 gallons per month. To come up with
the default figure per person, I divided the total miles traveled (2.3
trillion) by average MPG (20.36) and divided again by the number of
drivers in the U.S. (196 million), for 591 gallons per person. I also
use this in the right-hand column to come up with the amount of carbon
generated by an individual's driving.
On a separate page I have complete sources, references, and calculations.
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Most people are surprised to learn that the
typical diet (what people normally eat) uses twice as much energy to
produce than a typical vegan diet -- and therefore twice as much
energy-related pollution.
The reason is that livestock are food factories in
reverse: We put about 14 times more food into a steer than we get out
of it. So we're running 14x as many tractors, using 14x as much labor,
flying 14x as many crop-spraying planes, etc. (The reasons a typical
diet uses only twice as much as a meatless diet instead of 14x are that
other meats aren't quite as inefficient as beef, and that meat-eaters
also eat plant foods.) Here's how energy-intensive beef is: It takes 145 times more energy to produce beef than
potatoes.
Grass-fed beef is not the answer for a whole host
of reasons, the most important being that there is not nearly enough
grazing land in the U.S. to raise as much beef as Americans currently
eat.
Food choices are so important that the typical
American could save more much carbon by going vegetarian than by giving
up flying. Vegans do even better, saving twice as much carbon. (source) That's why I list Food higher in the
calculator than flying. It's also one of the easier lifestyle factors
to change. It's easy to choose a bean burrito instead of a hamburger.
It's not as easy to get from New York to California without flying.
One buzzword these days is buying locally-produced
food, so that it takes less energy to transport. While it can't hurt to
buy local, it's a small drop in the bucket compared to the effect as
going vegetarian or vegan. Transportation of food to the store accounts
for only 4% of the greenhouse emissionsn involved in producing the
food. A scientist who analyzed food energy in a research paper
concludes, "Buying local is not as important as what you eat."
In other words, it's much, much better to buy a pound of carrots
shipped from far away than a pound of locally-produced beef. (New Scientist
reviews the research paper, Actual research paper, source for the quote)
For the calculator, I assume that kids eat 60% as
many calories as adults (and therefore create 60% as much carbon).
On a separate page I have complete sources, references, and calculations.
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It's no surprise that planes use huge amounts
of energy -- and thus produce huge amounts of climate-changing
gases. The airlines are on the defensive about this and in their
in-flight magazines you will see big full-page glossy ads touting their
energy efficiency initiatives. What they're not telling you is that
such changes make only a 2% difference at best.
Most carbon calculators fail to include radiative
forcing (RF) and thus underestimate the impact of flying by a
factor of 1.9. RF basically means that the damage caused by planes
is greater than normal because the pollution happens up in the sky.
This calculator is one of the few to account for RF. RF is explained in
more detail in pp. 26-27 a Dec. 2006 PDF report from Tufts University, which states:
"To estimate the impact of an airplane
trip a multiplier should be used on the CO2 emissions from jet fuel to
account for full radiative forcing.... Although more research is needed
to fully understand the chemical processes in the stratosphere, the
research used by the IPCC is robust. We therefore recommend using a
calculator that includes a multiplier for the increased radiative
forcing in its carbon calculations."
Alternatives to flying include:
- Taking a train or bus
- Taking a cargo ship. (I've done that very thing, traveling
across the Atlantic Ocean by boat.)
- Vacationing closer to home
- Taking fewer trips, but staying for longer
periods of time
- Teleconferencing instead of face-to-face
business meetings
Would people consider not flying to save the
environment? Sure they would. A BBC
poll found that over half would do so.
In fact, most Americans already don't fly.
In a given year, only 43% of Americans take a plane. That number will
surely decrease as airlines respond to increased fuel costs by cutting
flights left and right (making travel less convenient) and raising
airfares substantially.
If you can't give up flying, let me give you an
out: the typical American could save as much carbon by going
vegetarian than by giving up flying. Vegans do even better, saving
twice as much carbon as flying. (source)
Many people come to this page looking for an
answer to the question, "Which is worse: driving or flying?"
The answer is flying. Planes effectively get only 22.6 passenger miles per gallon when
considering their special contributions to climate change. That's less
than just about any car.
The calculator asks for hours of flight rather
than miles because most people have a better idea of how many hours
they've flown than how many miles. The calculator averages the
number of miles you took per trip, since shorter flights use more
energy per mile than longer ones.
The default shown for flying by household is
equivalent to the total number of passenger-miles flown (848 billion
miles) divided by 107 million households, multiplied by the percentage
of trips that are personal (non-business), which comes out to 5548
miles, which I'm figuring as a 2 round-trips of 1,387 miles each way,
which is closest to 13 hours of flying time total.
On a separate page I have complete sources, references, and calculations.
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(see complete sources and
references)
The best way to reduce your carbon footprint is to
use less energy.
(Drive less, fly less, save energy at home, and eat vegetarian.)
The next-best way is to buy carbon offsets.
Tons of carbon dioxide
emissions per capita
(I got this from the Hinkle Charitable Foundation
which credits the Energy Information Administration,
"International Energy Outlook 2003", but I'm unable to find that
report, or a newer version, on EIA's website.
Wikipedia has a Carbon dioxide emissions per capita by
country article.)
Which actions make the biggest
impact
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Action (one person)
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Carbon Saved
in one year
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Stop driving
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6.0 tons
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Slash home energy use
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5.2 tons
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Go vegan
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2.2 tons
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Stop flying
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0.9 tons
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The average home pollutes more than the average car!
That's because the power plant burns dirty fuel to make our
electricity. The average U.S. home clocks in at 12.7 tons of carbon per
year, while a household's two cars come in at 11.6 tons. But in the
table I show that ditching your car has a bigger impact than slashing
your energy bill, because it's possible to get your driving down to
zero, but pretty damn hard to get your electricity and gas heating use
down to zero. However, we're really splitting hairs here: Driving and
home energy use are very similar and the potential savings are similar.
It's best if we reduce both, but reducing either one will have a big
impact.
Note that most people can save twice as much carbon
by going vegan than by not flying. This assumes 5.5 hours of flying
time per year.
The "reduce home energy use" line assumes using 150
kWh/mo. on average, and no oil or gas. (see sources)
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Passenger MPG
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Transportation Mode
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125.0
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Bus
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81.6
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Typical U.S. car, 4 people
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61.2
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Typical U.S. car, 3 people
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43.0
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Airplane, w/o considering
extra climate change effect
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40.8
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Typical U.S. car, 2 people
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22.6
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Airplane, after considering extra climate
change effect
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20.4
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Typical U.S. car, 1 person
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Flying is worse than driving
Planes get a respectable 43 passenger miles per
gallon (pMPG), but they cause 1.9 times as much climate change per
gallon of fuel burned, by virtue of their being up in the sky. So
when we consider climate change, the plane's efficiency is more like
22.6 pMPG. That's worse than most cars. And if there are two people
traveling in the car instead of flying, then the pMPG of the car is
doubled, while the plane is stuck at 22.6 pMPG, because we're already
figured the plane's pMPG on a per-seat basis. The only time that flying
is better than driving for a given trip is if there's only one person
in the car, and/or we're assuming a very low-mileage car.
The most efficient way to travel in the U.S. is by
bus. Inter-city buses get a whopping 125 pMPG. By contrtast, Amtrak
trains get only 45 pMPG (though that could be due to U.S. trains often
running very empty). (sources)
Hummer-driving
vegans use less energy than meat-eating Prius drivers?
Michael Pollan made that claim, but it's not true. The
calculator
can help do the comparison. A 10 mpg Hummer driven the U.S. average of
1000 miles/mo. generates 13.4 tons of CO2 per year, vs. 2.7 tons for a
50 mpg Prius, for a penalty of 10.7 tons for driving the Hummer. By
contrast, going vegan saves only 2.2 tons/yr. So it isn't even close,
it's far worse to drive a Hummer than to eat meat.
But this kind of comparison misses the point: Meat
production
really is energy-intensive and causes a tremendous amount of
unnecessary pollution, it's just that Hummers are even worse. Anyone
who's serious about reducing their carbon-, energy-, or
pollution-footprint is going to cut back or eliminate meat, especially
as it's the low-hanging fruit. Cutting back or going veg is the easiest
way for most people to make the biggest dent in their footprint.
Carbon Footprint Calculators
Compared
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Carbon
calculators compared
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Michael
Bluejay.com
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Nature.org
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EPA
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Carbon
Counter
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Carbon
Fund
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An
Inconvenient
Truth |
Interaction and Results
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All data & results viewable on same page
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✓
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✓
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✓
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✓
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Entire calculator viewable without scrolling
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✓
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✓
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✓
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Shows sample data and results right off the bat
with no clicks required
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Compares your (or your household's) results to the
typical American (or household), line by line
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(no, but
at bottom
of page)
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Shows total for each section separately, on the
same page
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✓
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✓
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Shows total of all sections
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✓
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✓
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✓
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✓
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Achieves brevity by omitting items that are <2
tons per person on average
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✓
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✓
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✓
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Fast
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✓
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✓
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Calculates automatically without having to click a
"Calculate" button
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✓
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✓
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✓
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✓
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No annoying/distracting animations
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✓
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✓
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✓
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✓
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Results are not wildly inconsistent with other
calculators
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✓
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✓
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✓
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Home Energy
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Allows you to enter your exact home energy use
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✓
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✓
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Allows entry of home energy in either energy units
or dollars
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Clearly shows whether data to be entered is per
month or per year
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n/a
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✓
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✓
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✓
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Doesn't require yearly data to be entered (who
gets a yearly electric bill?!)
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n/a
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✓
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✓
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Food & Driving
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Includes food section
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✓
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Shows driving & flying separately
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✓
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✓
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✓
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Allows you to enter MPG directly (rather
than making you specify four different things about your car so the
calculator can guess your MPG)
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✓
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✓
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✓
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Air Travel
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Includes air travel
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✓
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✓
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✓
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✓
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Doesn't restrict you to entering only one single
flight
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✓
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✓
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✓
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Good estimation of miles flown (not
just "# of short & long trips" or "number of hours" [without asking
for number of flights])
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✓
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Accounts for radiative forcing (i.e.,
results are not off by a factor of 1.9)
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?
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✓
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not by
default
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Other
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Sources and calculations provided and explained
well (esp. for "average person" figure)
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✓
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(mixes ind. &
household
figures)
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✓
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Shading is for the items I consider most
important.
Carbon
Calculator results compared (per household)
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Activity (tons of CO2)
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(this page)
(2.67-person household)
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EPA
(2-person household)
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Nature.org
(3-person household)
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CarbonCounter.org
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Home - Electricity
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9.5
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8.1
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Home - Gas
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2.4
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5.5
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Home - Oil
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0.8
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7.3
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Home - Total
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12.7
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-
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29.0
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13.2
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Driving
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11.6
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6.0/vehicle
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34.0
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9.2
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Flying
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2.3
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-
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3.3
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Eating
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11.7
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-
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12.0
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-
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Total
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38.3
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20.8
(27.7 for 2.67 people)
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75
(66.8 for 2.67 people)
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25.7
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Notes
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(a)
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(b)
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Carbon Calculators
results compared (per individual)
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Activity (tons of CO2)
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(this page)
(individual)
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CarbonFund.org
(individual)
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Nature.org
(individual)
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Home - Electricity
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4.8
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3.0
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Home - Gas
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1.2
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1.8
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Home - Oil
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0.5
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3.2
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-
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Home - Total
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6.5
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8.0
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9.5
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Driving
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6.0
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6.1
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12.0
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Flying
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0
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-
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Eating
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4.5
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-
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4.1
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Total
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17.0
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23.8
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27
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Notes
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(c)
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(d)
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Other figures for individuals (U.S./short tons):
- 22.5 tons - United
Nations, 2004
- 22 tons - Science Daily
- 21 tons - Carbon Trust, according to an article in The
Independent; note that I converted from U.K./long tons
- 8.0 tons - FirmGreen
- 7.5 tons - An Inconvenient Truth
(a) They figure the total
independently from the other figures; the total is less than the
individual values because the figures for natural gas/oil are only for
households that use gas/oil.
(b) Their calculator doesn't include defaults, so I had to enter my own
figures, so this total isn't really "their" estimate for household use,
since they don't tell us how much they think households use. (They have
a sources & references section, but it mixes individual and
household data, and we don't know how they'd separate that.)
(c) They cleverly figure the total by dividing the U.S.' carbon output
by the entire population. If you add up their line items, their total
is 14.1.
(d) Their total is higher than the sum of the line items because they
include a section on Household Waste, which I didn't include in the
table.
This page last modified March 201]
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