More info: contact John Robbins: jrobbins@queencity.com
AEA's president John Robbins will be taking his home office
off-the-grid! (Probably next spring). Just as in HOMEPOWER's April/
May 1997 article, "Doing a Load Analysis: The First Step
in System Design" by Benjamin Root, John's 1st step was to
analyze ALL power used in his office, from computers to lights
to printers and copiers. John's analysis quickly confirmed Ben's
2 simple laws of PV design:
(1) "Every watt not used is a watt that doesn't have to be
produced or stored" and
(2) "Every dollar spent for an energy efficient appliance
saves 3 dollars in renewable energy..."
This is because, unlike with utility power, most PV power costs
are in the initial purchase. Long term costs are usually battery-related.
"Paybacks" come from avoiding initial expenses.
John showed us that even though he had all EPA "Energy Star" rated computers and mostly compact fluorescent lights, the base case (first analysis) showed he would need 15 PV panels (at $300+ each) to power his office during cloudy December. This was too much! And most people would quit at this point and continue to draw from the utility but John is a fighter. Re-analyzing to reduce demand, revealed that by replacing his 2 desktop computers with notebook models, replacing the 2 remaining incandescent lamps with fluorescents, eliminating a few phantom loads (boombox and powerstrips which suck down power even when turned off because of standby mode heat making LED's!), eliminating a surplus electric clock, plus finally replacing both a copier and a laser printer with a single inkjet printer/ copier/scanner/ fax machine all in one combo which used only 22% the energy for copies and printouts, his PV panel need was reduce from 15 to 3 panels, for a savings of almost $4,000! This doesn't even include more savings from needing fewer batteries and other system hardware, all of which was also discussed.
This was a presentation of aggressive demand-side management, which was started in the "Off-the-grid PV community", not the utility programs of the late 80s and early 90s as many consumers might think! Pre-PV DSM (demand-side management) has been a routine part of design for off-grid PV.
Energy Star Ratings are useless:
John's recent research suggests that offices may use considerably
more energy per square foot than houses and other living
spaces. This may be, at least in part, because "energy star
ratings" on office equipment, the only ratings typically
seen by the buyer, mean almost nothing unless the computers are
left on all day, even at night. Such ratings do not have anything
to do with equipment wattage, which is why 15 watt notebook computers
have the same energy star rating as 150 watt desktop computers
and why 1,100 watt copiers have the same energy star rating as
30 watt copiers.
"Energy star rated" only indicates that the equipment
can power down into a less-power-consuming "doze" mode
when not used for extended periods of time. In most offices this
"Power Saving Feature" is usually overridden by the
user, as is often the case with screen savers.
Heat Generating Devices:
Offices have very high density of electric equipment. Besides
their own power consumption, this equipment generates heat which
forces higher cooling equipment size and operation costs, especially
in commercial and institutional buildings containing many offices.
For instance, for every 30 desktop computers replaced with laptops,
there's a potential savings of 1 ton of AC load and about 3.5
KW in electricity demand charges! Robbins thinks such savings
opportunities are overlooked by designers, building managers and
equipment buyers simply because they don't know there are such
opportunities.
When designing and planning an off-the-grid PV system, such aggressive down-sizing of the load demand cannot be ignored, because of the huge first-cost savings. Unlike the off-the-grid PV system experience, grid-intertied PV systems and other utility supply-side-only systems, neither offer this incentive nor educate designers and consumers about how such energy-savings opportunities exist which could reduce energy generation and pollution loads. This leads to the question that, "If DSM programs were important in the consumer movements of the late 80's and early 90's to hold off utility rate increases for building new generation, does it not indicate that it is even more important if that generation is more expensive, as with PV's?
John says he is fortunate in his design and energy engineering to address operations on the supply and demand sides within any process, unlike most designers, engineers, energy consultants and energy product retailers who commonly deal with one side or the other as a natural limitation of their authority or commission. Robbins sells no products and collects no commissions from sales or referrals. He offers small building design, analysis and consulting services, doing business as Robbins Alternate Energies since 1983. He is currently president of AEA and holds the education chair of the SW Ohio Chapter of the Association of Energy Engineers which honored him as Energy Engineer of the Year in 1994.
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