Wednesday, December 10, 2008

For the Energy Auditor

More and more people are now familiar with the term"energy audit", and that's a good thing.  With energy prices climbing, incomes shrinking, and the now undeniable (by anyone's standards) effects of global warming, we should all be getting energy audits.  Many utilities are now offering free or subsidized audits. You can do an energy audit yourself, but you will miss a lot, because a good energy auditor has a good tool bag.  He may have a blower door, an infrared camera, furnace testing equipment, etc.  Here are a few places to find that really thorough certified auditor  ENERGY STAR for Homes Partner LocatorRESNET Certified Rater Directory or FSEC's Energy Gauge Certified Building Energy Raters Directory.  
Now here's the rub - Many people who pay for the audit, and get the recommendations that are going to save them big bucks, never follow through by actually making those improvements.  Find a good insulation company, HVAC contractor, etc, and then look at your state's list to see if any rebates are being offered on the work that needs to be done. Here's a cool site for seeing what is available:  

For all of you energy auditors out there, we have just added a section on "Energy Auditing Tools" at our website

Thursday, July 31, 2008

Of Whole House Fans and Rebates

I've been doing a lot of research lately on whole house fans, and wanted to share some of my findings.  All whole house fans do one thing - and that is to bring night time air through the house and out through the attic.  This cools off the attic (that can get up to 190 in the summer) and the house as well. You close up the house in the morning to keep that night time air inside. Some things that make a whole house fan work better - multi-level homes instead of large one floor ranch houses, a tight home, willingness to open windows at night, close them during the day.
 Energy wise, a whole house fan is definitely a better alternative to an air conditioner in climates where nights are cool and days are hot.  As an example, a typical central air conditioner costs in the neighborhood of $3500.00. A low-energy insulated whole house fan costs in the neighborhood of $1000.00 The operating cost of a low energy fan is about .14/kWH in an area where the cost of a Kilowatt hour is .25 and a home is around 2000 sq. ft.  In the same area, same house, the cost per kWH for running an energy star central air conditioning unit is about $1.52/hour.  You save money, and help reduce strain on the environment.

  There are several things that are important to look at when buying a whole house fan (or, in my case, deciding which are the best fans to put on a website like ours -
1. CFM rating (cubic feet per minute of air that the fan will move)  A good rule of thumb is to purchase a fan with a CFM rating double the square footage of your home.  Many folks buy oversized, over noisy fans which leads to too much energy consumption, and an uncomfortable living environment.
2. Does the fan meet our requirements that it be a low energy user, and that it has some form of insulation that closes with a tight seal when the fan is not in use.  The fans that I've seen that meet this requirement are the Tamarack HV series, the Airscape, and the Quiet Cool fans, with the Tamarack providing the best insulation. 
3.  Is the fan quiet enough that it will actually be used, and still allow you to carry on a normal conversation in your home?  All of the above do this to a less or greater extent - the quietest being the Quiet Cool Series.

Yes, an air conditioner will work better for day time use for those of us living in a hot climate, but here are two options: One, use a whole house fan until inside air gets too warm, and then turn on the AC (maybe just a bedroom window unit). Two, if you live in a dry hot climate, use an evaporative cooler during the day for much lower energy usage.  Better yet, use a whole house fan with an Envirocool two part evaporative cooler.  The wet media and pump part of this swamp cooler is mounted in an exterior wall.  The second half of the swamp cooler, the unit pulling this cooled air through your home, is the attic mounted whole house fan.  Your home is cooled day and night while energy usage is kept to a minimum!  

See our website, for further info on low energy whole house fans  and the Envirocool.

By the way, in many states evaporative coolers, whole house fans, and many other energy efficient products are eligible for rebates and tax credits.  Here's an excellent website that let's you look at what incentives are available in your state.

Wednesday, June 11, 2008

Our Home Energy Audit

We at Positive Energy are lucky to live in Boulder, Colorado where energy audits are subsidized by the city.  Recently, I finally got around to having our own home audited.  Our home was built in 1912, so we expected that despite the fact that we had added insulation, changed out old windows, added a set-back thermostat, changed to compact fluorescent light bulbs, and had an on demand water heater installed, we might not receive top marks.
Our energy auditor, a private contractor, showed up with an infrared  gun and a blower door.  He installed the blower door in the opening of our front door, closed all the windows, and turned on the door's fan.  This pressurized  our house - he could then go around with a smoke stick and see where the leaks were.  He used the infrared gun to look at the insulation in our walls and ceiling.   
Our house looked better than we expected!  We got extra points for living in a home that is only 1500 square feet - much smaller than average for our community.  The only further step that our auditor recommended was to insulate our basement walls - a job we don't want to take on - we'll contract that out as well.
For more information on Boulder's subsidized energy audits, see
For more information on set-back thermostats, on demand water heaters, compact fluorescent light bulbs, and much much more - see our website,

Wednesday, May 7, 2008

Our Neighborhood Goes Green

     As the owner of Positive Energy and The Green Builder's Catalog ( my business interests spill into the rest of my life.  I am fortunate to live near neighbors with similar energy saving concerns.  We are all interested in "greening" our community. What can a community do to enhance their "greenness"?  Our neighborhood of about 1000 homes has formed a committee to investigate and take action.  Here are some of the steps that we have taken.  
     We started by delivering flyers to every home in our neighborhood, announcing a kick off meeting featuring a major speaker (Hunter Lovins - who lives in Boulder, our town).  At the meeting, we got folks to sign up for home energy audits, gave them some compact fluorescent bulbs (thanks to the Climate Smart city program) and gathered e-mail addresses.  
     Our latest initiative is the launching of a "Community Roots" program.  Buying food close to home is optimal in terms of what is best for the planet, and you can't get more local than this! We are signing up folks in our area with large yards to be program "hosts". Neighbors and the small Roots staff would farm the yard.  The home owner reaps all the vegetables that they need, with the rest going to neighbors who buy a share, and help to work the land.  I'll let you know how this works out.  For more information, check out their website at
     Future projects include energy related movie nights (maybe on an outdoor screen in the summer), a car share program, "The Biggest Loser" neighbors' low energy users competition, and anything else we can think of - ideas welcome.  If you want to learn more about what we are doing, check out the "Greenlands" portion of our website,