Keeping Cool and Staying Green

Personally, I’m keeping cool with a weekend trip to Newport, RI for a wedding (which is why I didn’t blog much today).  But traveling to keep cool may not be the greenest way to go.  Following the eighth warmest winter on record, the summer of 2009 is looking to be a hot one (see Breaking: NOAA puts out “El Ni±o Watch,” so record temperatures are coming and this will be the hottest decade on record). Constantly using your air conditioning to keep cool can consume a great deal of energy and release greenhouse and ozone-depleting gases into the atmosphere, but you can maximize your energy efficiency by following these six tips that will help you stay cool (from a post first published here):

Consider other options before cranking up the AC. Save energy and money by using ceiling fans or portable fans, which can make a room feel six or seven degrees cooler. On milder days, fans alone may keep you cool enough, but on particularly hot days, try setting the AC to 80 degrees and letting the ceiling fan to do the rest of work. Remember, though, fans cool you, not the room, so running them when you aren’t in the room is just a waste of energy. Before holing up inside your home and turning on the AC, you could also consider going somewhere that already has it. After all, businesses and public buildings run their AC whether you are there or not. Libraries, movie theatres, and coffee shops are just a few places you could go to keep cool and entertained.

[JR:  I have six (!) ceiling fans in my home!  We also have a retractable awning, a popular feature in Europe, but hasn’t quite caught on in the U.S. — yet.  And don’t forget that white/reflective roof (see “What is geo-engineering and adaptation and CO2 mitigation all in one?]

Seal and insulate your ducts. Most central air conditioning systems are more efficient than window units, but the typical home loses about 20 percent of the air that moves through its ducts because of leaks, holes and poorly connected ducts. For more information on what you can do, see the Department of Energy’s list of frequently asked questions about insulation and duct sealing. You can also seal your windows with a window sealing kit available at the local hardware store to keep cool air inside, or even upgrade the insulation in your walls.

Buy the right AC for your space. Bigger is not necessarily better when it comes to AC units. Larger units do not provide the best cooling, can waste energy and money, and are more expensive to own and operate than smaller units. If your unit is too big for your space, it will turn on and off frequently, reducing its efficiency and increasing wear and tear on the appliance. Buying an Energy Star-certified unit will help regulate temperature and save energy. A model with a timer is another option, and a programmable thermostat and sleep settings will also help keep energy consumption low. Tax credits may be available for new AC units depending on the model. Be sure to check out what’s available before making a purchase.

Position your unit well. Keeping heat-generating appliances away from your AC’s thermostat will prevent the unit from working too hard and overcooling the room because of inaccurate readings. Window units should be placed in windows with the most shade cover, but also make sure that any window coverings do not block the unit’s airflow.

Be mindful of running your car’s AC. The impact of your car’s AC varies depending on the type of driving you are doing. Highway driving has the least impact. Consumer Reports found that running your car’s air conditioning while traveling at 65 mph reduces gas mileage by about one mile per gallon. Rolling down the windows did not create a measurable change in gas mileage while traveling at the same speed. City driving with the air conditioning on will have the greatest impact on fuel consumption. Drivers should also be mindful of the length of their trip. Your car’s AC impacts your fuel economy the most when you are using it to cool an already hot car, so you would do well to roll down your windows for short trips instead of running the AC.

Take care while performing maintenance on your car’s AC. The refrigerants found in most mobile AC units are an improvement from those of previous generations, but they may still be damaging to the environment. Recent research indicates that R-134a, a common refrigerant found in automotive AC units, is collecting in the atmosphere and could be contributing to global climate change. It is unlawful to release R-134a into the atmosphere, and consumers should be careful when performing maintenance on their car’s air conditioning units.

13 Responses to Keeping Cool and Staying Green

  1. Rick Covert says:


    It will be a little hard to keep the A/C off here in Houston. The temperature topped off at 100º F today.

    I have taken your advice to heart though. Just this last winter I changed out a burned out attic fan, sealed the seams in my house, sealed up the rear door and installed temperature reflecting curtains in the master bedroom which are supposed to reflect 25% of the heat from the sun beaming through the windows. My wife has noticed the temperature reduction with the last addition. I have also installed an electronically timed thermostat and now I’m eargerly waiting this months utility bill to see if it has made a difference.

    I’m wondering though since refrigeration change to R-410A occurs January 1, 2010 if they will be more efficient than the R-22 units they are replacing or is there no change in efficiency and this changeout is being done to exclusively protect the ozone layer? If this is so how much bang for the buck is there from R-410A?

  2. Rick Covert says:

    Oh, one more thing. Ceiling fans in Houston homes are a common feature. My house had 2 fans when I moved in and I installed 3 more and they do make a difference.

  3. Gail says:

    Joe, while in Newport, if you have time try to visit some of the historic homes. They are fabulous, and there is a wonderful long trail to hike along the sea that is just dazzling.

    Also please look at the trees. When I was there last summer, they looked pretty bad which is tragic, because so many of them count their years in centuries.

  4. Peter Croft says:

    It is almost unheard of to have permanently installed A/C in a domestic situation here in the UK.

    I don’t know whether to feel all green and virtuous or a bit third world.

  5. Gail says:

    Peter, it doesn’t get nearly so hot in the UK, that’s why! So you are neither particularly virtuous, or deprived. You have a very mild climate (or have had, at least so far) without extremes of hot or cold, which is why so many splendid gardens thrive in Cornwall for instance, with all sorts of tropical plants that succumb to more extreme temperature variations elsewhere.

    But some of it is just expectations. I can remember back when having A/C in a car was a rare luxury that I scorned. When we got into the car to go home from the beach in Massachusetts where I grew up, oh so many years ago, it was like clambering into an oven, and even with all the windows open, we would sweat all the way home.

    Now people let the car run and spew noxious fumes into the air before they will start to drive.

  6. Omega Centauri says:

    I’m huffing and puffing cause I just put a roll of R19 into the attic, I’ll worry about putting it down (as an extra layer beyond what is already there) tommorow morning. I got a couple touches to finish with the radiant barrier first. Hopefully these mods will make a substantial effect. Our central valley like climate is very hot, and usually no summertime clouds whatsoever. But, this year a persistant west coast trough is keeping things cool windy, and sometimes even cloudy. Haven’t needed the air for weeks now.

    For those living in a dry climate, letting in cool air at night -fan assisted if the nighttime cold and wind is marginal can bank enough coolness in a house to delay the need for AC until late afternoon (or in decent weather, until the evening cooldown). Just by being a little bit smart, and not just relying on the thermostat, you should be able to cut you cooling bill in half. My insulation project will hopefully cut that in half yet again.

  7. John says:

    Have not needed the A/C here in the Northeast. For June, heating degree days far exceed cooling degree days in our little corner of Connecticut.

  8. Neil Howes says:

    Great advice about ceiling fans, we use ours but also a little A/C to reduce the humidity.
    Good energy conservation doesn’t have to mean being less comfortable any more than reducing CO2 means only using less energy, replacing coal and oil with renewable energy has to be the main strategy, with energy efficiency speeding up the process.

  9. Henry says:

    You have a lot of helpful ideas listed here! Another altnerative would be to install a geothermal heat pump . They cut energy bills in half and with the tax incentives available, they are becoming quite affordable. It’s great to see people trying to tackle our energy problems!

  10. Donald B says:

    An additional way to save energy in both winter and summer is to install a Heat or Energy Recovery Ventilator (HRV/ERV) system for your house. As always, there is an advantage in doing it in new construction, but this takes house air and puts it through a heat and/or humidity (enthalpy energy) exchange with the air being brought into the house to replace it. Thus in summer the humidity/heat is extracted from the incoming air to the outgoing air and in winter the opposite happens. This saves the work (energy consumption) of the cooling/dehumidification process in the air conditioning process in summer and some of the heating/humidification process in winter.

  11. Peter Croft says:


    Well, yes – it is about expectations. That’s part of the problem. A typical citizen in Africa or India would experience the same extremes of temperature as in the US but mostly has no expectation of A/C. On the other hand, when the debate is conducted on an American blog it is a given before the debate has even started that A/C is a non-negotiable basic human right. (OK – bit black and white, but that’s basically the picture).

    We spent a couple of weeks in Florida – in August – about 10 years ago (before I worried about cc I hasten to add). Very, very hot and very, very humid. In the short time it took to sprint from the A/C’d car to the A/C’d house my glasses so completely steamed up so I could’t see anything! My conclusion – some places are carbon intensive places to live. Maybe people should think about moving.

  12. Peter Croft says:

    “Have not needed the A/C here in the Northeast. For June, heating degree days far exceed cooling degree days in our little corner of Connecticut.”

    The point I’m making is that in the UK we don’t have cooling days. We just get hot and try and pretend we enjoy it. Forecast is 27 deg C in London today (81F) and its only June.

  13. Kim says:

    If people really want to go green and stay cool they need to trade in that central air conditioner for a geothermal system.