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Home Energy Magazine Online March/April 1993
LETTERS
Gas Heat Pumps Not So Hot
Nance Matson's informative article "East meets West: Gas Fired Heat
Pumps" (HE, Sept/Oct '92, p. 33) refers to the proliferation of natural
gas heat pumps in Japan but fails to point out Japan imports virtually all of
its coal and gas and therefore encourages a balance between the consumption of
natural gas and electricity, quite a different situation than in the United
States. The article also states that "In Japan, under the influence of
governmental policies geared to improve (emphasis added) energy
efficiency, gas cooling has been installed in 80% of new buildings." Contrary
to this statement, gas cooling typically uses more source Btu than electric
cooling. Perhaps the author meant that the Japanese government wants to balance
the energy supply rather than improve energy efficiency with gas cooling.
An electric heat pump, under normal operating conditions, does not require
electric motor servicing during its lifetime. On the other hand, as the article
mentioned, a natural gas heat pump engine must be serviced at least once a year
(two filters, spark plugs, tune-up). It may require two sets of technicians for
servicing--one for refrigerant loop, the other for the engine--and this will
probably increase maintenance costs. Since customers typically have poor home
maintenance records, the cost of proper maintenance and the consequences of
improper maintenance should be central to any comparative analysis.
The author states that "GRI estimates energy cost savings of 20% to 80% over
comparable conventional electric heat pumps and furnace/ air-conditioners," but
the table on estimated energy savings does not refer to energy cost savings.
Also the table shows savings only up to 60%. And only Chicago, with a short
cooling season, and Phoenix, with high electric rates, are discussed; energy
savings are not discussed for other locations listed in the table on field test
efficiencies.
The article claims that "York gas engine heat pump has an equivalent
(emphasis added) Heating Seasonal Performance Factor (HSPF) of 14.0 and an
equivalent Seasonal Energy Efficiency Ratio (SEER) of over 15.0." While this
provides a very favorable impression of this type of equipment, these ratings
are based on the cost of natural gas, rather than it being a thermodynamic
quantity. You should clarify what the stated equivalent rating means.
A natural gas heat pump produces emissions on site that may exceed future local
air emission standards. Also, emissions from an on-site natural gas heat pump
depend on an air to fuel ratio which changes during a cold start-up, with
important health implications for home dwellers. If higher emission standards
are required, they can be phased-in at power plants much easier and cheaper
than for a large number of gas heat pumps.
Finally, it is questionable if a natural gas heat pump will help a homeowner or
the environment. It will certainly not help an electric utility that will lose
the off-peak load, will decrease load factors, and therefore may increase
utility rates. Also, we do not understand how a natural gas heat pump will
benefit regulators.
Matt Chwalowski and Rick Tempchin
Edison Electrical Institute
Washington, D.C.
Author Nance Matson responds: While the United States and Japan face
different energy demand and resource problems, both have undertaken intensive
programs to improve energy efficiency, including development of high efficiency
electric and gas technologies such as the gas heat pump. As for the
effectiveness of gas cooling, utilities, both gas and electric, recognize it as
a means to reduce summertime on-peak electrical demand. Also, after
accounting for power plant efficiency, source energy consumption is higher with
electrical equipment. In addition, by contrasting the maintenance requirements
of gas and electric heat pumps, the writers ignore the fact that present HVAC
equipment typically goes without adequate servicing, lowering efficiency and
raising operating costs. Besides the spark plugs and tune-ups for gas heat
pumps, why leave out correctly charging heat pumps and air conditioners with
refrigerants, cleaning coils, and adjusting furnace burners?
The 20-80% savings figure, provided to me by Gary Nowakowski of GRI,
represent cost savings estimated from test houses throughout the U.S.,
as do the figures in the table which presents only two selected localities.
HSPF and SEER are efficiency levels that a standard heat pump must achieve in
order to exhibit the same operating costs as that of a gas heat pump, in U.S.
DOE's Region IV, taking thermodynamic performance as well as energy costs into
account.
Editor's Note: On the subject of gas versus electricity source energy, see
the box "Fuel Switching and Source Energy," p. 15.
Well Dressed Weatherizer
It happened while performing some draft detection using the fan
pressurization/depressurization method. I was on the trail of some thermal
bypasses in the kneewall attic, the homeowner following right behind me as I
crawled along.
Suddenly she burst into laughter, for no apparent reason. Kneewall attics not
being that funny, I inquired as to the reason for her mirth.
It turned out that she had discovered the answer to the question "What kind of
footwear do blower door sleuths wear?" "Air Escape," of course, the name quite
prominently printed on the bottom of my Nikes!
Larry Hasterok
Wisconsin Energy Conservation Corp.
Madison, WI
PG&E Lighting Program Drawbacks
I think it is great that the utility companies are making compact
fluorescent lights available at reduced prices. However, consider Pacific Gas
and Electric's (PG&E) current program to make Osram, GE, and Lights of
America lamps available through retail stores for under $10 each. A promotional
flyer in my October PG&E bill supplied a number to call for a list of
participating retailers.
I searched for two weeks on foot and by phone and did not find one local store
that actually had any compact fluorescents. In each case, I asked to speak to
the manager and explained that their store was on PG&E's list. Most said
they had not heard of the program.
Very few stores on the list plan to carry more than one of the three brands.
Having three brands (each having a different shape) is a real strength of the
program, but it is not nearly as useful if they're not sold together in the
same stores. A variety of sizes and shapes allows consumers to accommodate
compact fluorescent lights to practically all outlets. QLux, GE, and Panasonic
lamps with diffuser globes are typically wider (about 3 in.) and shorter than
the bare lamp Osram, Prolight, and Panasonic varieties. Lights of America
circline bulbs fit around the harps of ordinary table lamps.
Also, according to the information provided with the PG&E list, most stores
will carry only the GE bulbs. Many San Franciscans, including myself,
participate in a boycott of GE products.
Pamela G. Coxson
San Francisco, CA
Editor's Note: Ms. and Mr. Coxson's house, fully fitted with
energy-efficient measures as well metering equipment, was the subject of an
earlier article (see "One Family's Electricity Savings," HE, May/June
'92, p. 10).
Turn On, Tune In Savings
We've developed a partnership with a local television station's news
department. We now have a weekly spot on energy conservation on one of their
news shows. We're excited by the success of the project and feel it could be
duplicated in other markets.
The partnership is part of our newest residential energy conservation program,
"Power for Pennies," which also includes a workshop series. Jacksonville
Electric Authority produces a segment on energy conservation for WTLV's "Good
Morning Jacksonville--Saturday," a weekend version of their
Monday-through-Friday news and information program. The program airs from 8
a.m. to 10 a.m. and then it is repeated from 10 a.m. to noon. Each Saturday,
viewers see information on duct leakage, cleaning air conditioner coils,
air conditioner filter maintenance, repairing water leaks in toilets, the
impact of hot water leaks, insulation, surge suppressors, customer thermometer
tests, pool pump timers, and more.
The project consumes only 50-60 person-hours per week using two employees
part-time, but it reaches some 36,000-40,000 viewers per week. In comparison,
two full-time energy auditors (80 person-hours) reach 35-45 people per week.
With a cost of less than 5cents per customer contacted, it can be
cost-effective. Since JEA is a municipal utility, and is prohibited from paying
for advertising, "Pennies for Power" is produced as public service.
Perhaps the most effective aspect of this project is the method of presenting
information. Hearing a customer say, "My bill was four hundred dollars! I just
started crying!" sounds far more interesting than hearing an engineer talk.
Bruce Dugan
Jackson Electric Authority
Jacksonville, FL
Environmental Directory
Our Salt Lake Valley Environmental Resource Directory 1992-93
contains approximately 90 categories and 100 sub-categories of goods and
services relating to energy efficiency and healthy living in the Salt Lake
Valley.
The directory had its origins when our clients would ask us for the completion
of our energy efficiency and environmental assessment of their residence, or
where they could go for goods or services. So we sat down and planned to put
together the directory in a month--and the project turned into a six-month
undertaking!
I thought other Home Energy readers may like to know about the directory
so that they could possibly develop similar directories in their areas. If they
would like to receive a copy, we can make it available to them for $4 which
includes postage and handling.
Wesley A. Groesbeck
Environmental Resources
Salt Lake City, UT
Editor's Note: Readers can obtain the directory from Environmental
Resources, 2041 Hollywood Ave., Salt Lake City, UT 84108. Tel:
(801)485-0280.
CORRECTION
The article New Standards Begin, But Will Rebates Continue" in the
Jan/Feb issue of HE should have stated the formula used to calculate
"adjusted refrigerator volume" as follows:
Adjusted volume =
refrigerator volume + (1.63 2 freezer volume)
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