kohilo

The Kohilo Whole House Fan is designed to be more financially available (yes, that is a genteel word for cheaper) than our flagship units. How did we do this ? We replaced the motorized damper unit and electronics board with a backdraft damper.

A backdraft damper is pushed open with airflow and falls back (by gravity) when the fan is off. This provides a basic seal (nothing like our motorized dampers), but has no insulation.   In severe climates the Kohilo grille will have to be manually insulated at the end of the season.  We do provide an upgrade path for customers so that they can upgrade to the full AirScape functionality and convenience.

Railways should be open sourced.

Even though railroads are much more energy efficient and deliver lower transportation costs without federal subsidies, why are trucks the preferred mode of transportation?

I think that the answer lies in the fact that the highway truck combination is effectively open source.  The term open source is commonly used in the software world, but it applies here as well.

The platform is a highway, which just about anybody can use, provided they obey rules for weight, size, and safety of their modules (trucks in this case). This gives a tremendous amount of freedom to truckers and shippers to control their own destiny.  Ask anybody who has used the railroads for shipping and you will see that a rigid central planning department controls how and when your freight arrives.

How about this for an idea. Let’s make the railroads into a regulated monopoly. (It works for electricity, water, and gas BTW). The railroad makes its income by maintaining the infrastructure.

When you have a hammer…

“When you have a hammer, everything looks like a nail”

What a wonderfully simple way to describe much of our world.  I am reminded of this whenever I see people working on the “energy” problem.  Software people clearly know, that if only we wired everything up and monitored our energy use, the rest of the problem would be trivial.  Economists clearly have the upper hand, because they can describe carbon trading as the sure fire method to reduce carbon output,  increase energy efficiency, and still have economic growth.  Photovoltaic manufacturers, electric car builders, and wind farm developers are among the many queuing up at the public feeding trough.

Nothing wrong with any of those solutions.  Just bear in mind the aphorism.

By the way, our hammer is a whole house fan.

Is this the best stimulus we could think of

Our government program to encourage home buying is coming to a close.  Was it as good idea ? Certainly, it was for real estate agents! At least with the “cash for clunkers” program, the country as a whole (possibly) benefited by encouraging production of new, efficient cars and the retirement of low MPG cars.

Why didn’t we do the same thing for houses ?  OK, not the same thing, but how about this idea (in case we’re crazy enough to exend it):  Pay out the $8,000 directly to buyers of newly built homes.  For buyers of used houses, put the cash towards sealing, and insulating, and generally making the old house efficient.  Either way, contractors and their employees are working.

I will name this complicated economic concept “Have something left after the party’s over” , with the other very, very complicated concept (especially not  understood by bankers) “Spread the wealth”.

First pass on energy savings

We’re getting ourselves ready to build some software to help predict whole house fan energy savings. In the meantime, I put together this spreadsheet, which I think is a pretty good approximation for the coastal areas of California.

Potential Whole House Fan Energy Savings per Year for California





Input Energy cost arrow $0.24 Dollars per KWH
Application High Speed Watts Low Speed Watts Energy Savings * (per Year)
2.5WHF 288 250 $777.89
2.5eWHF 200 43 $826.70
Air Conditioning 2808 na $0
* Assumptions are that the cooling season is 5 months, the WHF is run 10 hours/day, 40% use is at low speed, an average deltaT at night is 10º , and that all WHF cooling offsets AC use.

A tale of two houses

It was the best of times, it was the worst of times. (Don’t worry; that’s the end of the literary pillaging.) I poked my head  outside this afternoon at 5 PM, thinking that maybe I should open the windows to warm the place up a little. As I go outside, I noticed that the neighbor’s AC unit was running. The inside temperature in my home was 72º, outside was 88º.  So why am trying to warm up and the neighbor cool down?

Several reasons as it turns out.  I’m living in an ICF (insulated concrete form)  house that has one of our whole house fans installed. Whereas the neighbor’s house is a  low mass stick framed house, and certainly has no whole house fan.

Of course whole house fans are great – but what seems to be a great combination is lots of mass to store “coolth” (made up word meaning the opposite of heat). I’ve been able to survive quite well all summer with just a whole house fan for cooling – no AC.  That said,during the second week of 105º  days, AC would have been nice for about 4 hours per day.