[Greenbuilding] energy and power terms

Gordon Howell -- Howell-Mayhew Engineering ghowell at hme.ca
Sun Nov 20 11:01:31 PST 2011


Hello Gennaro:

I can appreciate your comments about the green building list being 
about green building.  My read of it was that Nick was responding to 
the incorrect use of "kilowatts" to refer to energy -- and I agree 
with Nick and the strength of his comments re the misuse of 
kilowatts.  I am on a similar rant against this misuse -- even with 
electric utilities and electricity regulators (imagine!).

Frank Tettemer should have said "kilowatt-hours".  I am amazed at how 
many people mix up the terms "kilowatts" (of power) and 
"kilowatt-hours" (of energy) ... we don't mix up "kilometres per 
hour" (of speed) and "kilometres" (of distance) (or "miles per hour" 
and "miles") so why do we mix up energy and power?  ("power" is not 
electricity in the slightest... electricity is electric charges)

Power (watts, W), speed (kilometres per hour, km/h), electric current 
(amperes, A) and frequency (hertz, Hz) are respectively merely rates 
of change in energy (joules, J), distance (kilometres, km), electric 
charge (coloumbs, C) and states (cycles of anything), but people seem 
to be commoditising power as if it is something that is bought and 
sold.  This is getting a lot of people really confused, 
unfortunately, when it is instead a very simple concept.

The only reason why there is any issue with this is because the 
Sumerians developed the sexagecimal system over 4000 years ago 
<http://en.wikipedia.org/wiki/Sexagesimal> that gave us 60 minutes 
per hour... (thanks guys)

I welcome anyones comments.

+Gordon Howell, P.Eng.
Edmonton




>Date: Fri, 18 Nov 2011 17:57:24 -0500
>From: Gennaro Brooks-Church - Eco Brooklyn <info at ecobrooklyn.com>
>To: Green Building <greenbuilding at lists.bioenergylists.org>
>Subject: Re: [Greenbuilding] Fwd: energy savings myths
>
>This list is about green building. not just energy. learn the distinction.
>its about time you did.
>
>Gennaro Brooks-Church
>347-244-3016
>
>On Nov 18, 2011 5:43 PM, "nick pine" <nick at early.com> wrote:
>
> > Gennaro Brooks-Church - Eco Brooklyn <info at ecobrooklyn.com> wrote:
> >
> >  After building a Passive House in NY I learned it only needed insulation
> >> to code - R18. What made it or broke it was how well the 6mil plastic air
> >> barrier was sealed. Just a one inch hole in the plastic rendered the house
> >> unable to heat with the tiny mini-splits. Seal the hole and you can heat
> >> the house with a hair drier.
> >
> > Absolute bull****! Hogwash! Rubbish! Nitwit! Try using actual numbers!
> >
> > Frank Tettemer <frank at livingsol.com> wrote:
> >
> > Even having been experimenting and physically working on these questions
> > for over fourty years, it has taken most of a generation of time to cut
> > our household's daily energy consumption to two armloads of firewood,
> > about a dollar's worth of propane, and two to four kilowatts of
> > electricity per day.
> >
> > More absolute bull****... Kilowatts are power, not energy. This list is
> > about energy. Learn the difference between power and energy!
> >
> > Nick




More information about the Greenbuilding mailing list