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					                                                COOL SOLUTIONS FOR GLOBAL WARMING

                                   NATIONAL TOUR OF SOLAR HOMES
                       When It Comes to Solar Energy, Maine Home Shines

PROJECT SNAPSHOT                            INTRODUCTION                                            While the 480-square-feet of panels on

                                                       he electric power grid links gen-      half of the roof focus on the single task of
                                                       erators and consumers together         producing hot water, the 16 panels on the
Solar home
                                                       with wire. But it is a system          other half serve as an electric power plant,
                                                       plagued by inefficiency, and by        sending 48 volts of direct current to a
                                            environmental risk. Line losses alone may         basement inverter, which converts it to
4.2-kilowatt ASE photovoltaic modules,
                                            average five percent of total output, and         240 volts of alternating current.
passive solar design, solar hot water
                                            power generation is notorious for its myri-             The house cost a total of $300,000 to
system, and high-efficiency insulation
                                            ad environmental impacts: acid rain, dead-        build. All told, the environmental features
and windows.
                                            ly particles, ozone smog, toxics – not to         described here accounted for $32,000 of
                                            mention global warming.                           that, or a little more than 10 percent. The
                                                Imagine, if you will, an alternative grid –   architect was Solar Design Associates of
6,800 pounds annually                       a system that joins generator to consumer,        Harvard, MA, and Spang Builders was the
                                            one that is linked to others not by wire but      contractor.
INVESTMENT                                  by wisdom. That, in essence, is what the                For each of NESEA’s tours – and the
$32,000 for all of the above energy-        Northeast Sustainable Energy Association          Lord house was no exception – homeown-
saving technologies                         (NESEA) does each year when it helps to           ers were on hand to answer questions,
                                            organize the National Tour of Solar               offer information about construction and
LESSONS LEARNED                             Homes. The idea is simple: find private           renovation, discuss operation and mainte-
s To get the most out of the sun, a
                                            homes and businesses that showcase the            nance issues, and describe what it’s like to
home should be properly sited, and          effective use of solar power, and open            live in close proximity to renewable ener-
then designed to take advantage of          them up over a weekend for a free public          gy technologies. The Tour showcased a
the available solar energy.                 inspection. The Tour is an annual, nation-        wide variety of buildings, from rural and
                                            wide event, and for the past five seasons         remote single-family houses to urban
sNet metering is central to the             NESEA has been its prime sponsor in nine          multi-family dwellings and businesses.
economics of on-site electricity            Northeast states. This year NESEA organ-          They were of many sizes and price ranges,
generation.                                 ized 165 owners, and worked on publicity          from small self-sufficient cabins and sub-
                                            and coordination with local sponsors.             urban family homes, to large, custom-built
sSome energy-saving technologies                                                              residences, and commercial stores and
have much shorter payback periods           PROJECT DESCRIPTION                               offices. The Tour focused on a range of
than others.                                One of the most noteworthy homes on the           technologies as well, including passive
                                            tour is William Lord’s 2,900-square-foot          solar and climate-responsive buildings;
s New construction allows all of the        residence in Kennebunkport, ME. Built in          active solar systems (among them,
energy-efficient features to be carefully   1995, Lord’s home incorporates a number           domestic hot water and solar electric sys-
integrated into the home’s overall          of highly efficient, environmentally sound        tems (photovoltaics)); hybrid systems
efficient design.                           technologies. The house has been recog-           that incorporate more than one power
                                            nized many times for the effective way it         source, such as wind or micro-hydro; and
FUNDING SOURCES                             integrates an array of photovoltaic (PV)          energy-efficient buildings that consume
Homeowner                                   panels directly into its design. The roof         little electricity and have low energy costs.
                                            incorporates 4.2 kilowatts (kW) of PV
                                            modules manufactured by ASE Americas,             THE RESULTS
                                            Inc. The house also employs a solar hot           The rooftop PV generating system typical-
                                            water system, an air-to-air heat exchanger,       ly produces more than 4.5 megawatt-
                                            radiant floor heating, low-consumption            hours (MWh) of electricity each year,
                                            plumbing, a fresh-air intake, passive radon       roughly 590 kWh more than the home
                                            mitigation measures, high efficiency (R-8)        uses. Comparing the Lords’ February
                                            windows, vented walls that extend the life        2000 energy costs with those of a neigh-
                                            of the siding and stain, and propane back-        bor illustrates the extent of the savings:
                                            up for heating, cooking and clothes dry-          the Lords spent a total of $46 dollars that
                                            ing. The solar-heated water feeds the tap,        month; the neighbor shelled out $540.
                                            and provides heat by circulating through          As noted, the Lords rely on propane for
                                            radiant tubing built into the floors on the       cooking, drying clothes and, infrequent-
                                            first and second levels.                          ly, backup heating. At the neighbor’s, all
                                                                       COOL SOLUTIONS FOR GLOBAL WARMING

heat is provided by burning oil. Based on                        local utility cost of $0.12 per kWh, the                          dedicated website (the URL is listed
this comparison, the Lords’ energy-sav-                          family saves $40 a month – and $500                               below). For its part, NESEA’s plans for
ing features will pay for themselves in                          annually – on electricity costs alone.                            2001 include its sixth year in a row as the
just over 57 years. Nonetheless, the fami-                           By generating roughly 4,500 kWh of                            Northeast’s prime sponsor of the
ly was very interested in incorporating                          emission-free electricity each year, the                          National Tour of Solar Homes.
some of the most advanced and costly                             Lords’ solar system avoids some 6,800
technologies – such as the roof-integrat-                        pounds of CO2 emissions. This is equiva-                          ORGANIZATIONAL PROFILE
ed PV system – both to show that they                            lent to the CO2 associated with driving                           The Northeast Sustainable Energy
indeed work, and to gain valuable experi-                        about 7,650 miles in a typical passenger                          Association is a regional membership
ence in how they work. The average fam-                          car. The system also avoids nine pounds                           organization. Its members include engi-
ily looking to build a new home is not                           of NOx that otherwise would be emitted                            neers, educators, builders, students,
likely to incorporate all of these meas-                         by the regional electricity system each                           energy experts, environmental activists,
ures. But some – high-efficiency insula-                         year, and 28 pounds of SO2 .1                                     transportation planners, architects and
tion and windows, for example – offer                                                                                              other citizens interested in responsible
much shorter payback periods, and in                             LESSONS LEARNED                                                   energy use. NESEA’s overarching goal is
fact are being incorporated into more and                        The construction and operation of the                             to bring clean electricity, green trans-
more new buildings.                                              Lord’s home offers several key lessons:                           portation, and healthy, efficient buildings
      The Lord house also highlights an                                                                                            into everyday use in order to strengthen
important energy policy issue, the impor-                        s The most important initial decision is                          the economy and improve the environ-
tance of a little-known regulatory pro-                          to find a piece of land that maximizes                            ment. The focus of its programs and
gram known as “utility net metering.”                            solar gain – both as a function of weather                        activities is the northeastern United
Under net metering, a customer who                               and of potential home design.                                     States, from Washington, D.C., to Maine.
generates electricity on-site essentially
can sell it back to the utility during times                     s For a PV array to be a sensible invest-                         CONTACTS
when the customer is generating more                             ment, it is essential to be able to arrange                       Interested members of the public may call
than he or she needs. The customer                               for net metering from the local utility.                          or send an e-mail to receive a free infor-
receives a bill for the energy used each                                                                                           mation packet, which includes materials
month net of the energy generated back                           s Some technologies incorporated into                             about the National Tour of Solar Homes
into the grid. This billing arrangement                          the house are very cost effective, offer-                         and how to build a solar home. The toll-
makes home generation far more cost                              ing payback periods as short as a few                             free number is 1-877-44-SOLAR, and the
effective, since excess energy is sold                           years. A homeowner who wants to save                              e-mail address is jtauer@
rather than lost. Maine is one of about 20                       energy and cut CO2 emissions need not
states that currently require utilities to                       incorporate all of the systems that the                           The website for the Lords’ home is:
offer net metering arrangements to cus-                          Lords did.                                              
tomers, and this was a significant factor
in the Lords’ decision to invest in the PV                       s With new construction, a number of
array. To get a sense of its impact, con-                        efficient features like a passive solar sys-                      1 All emission reductions cited here are calculated
sider this: If the Lords were to sell back                       tem can be “designed in” from the outset.                         based on New England Regional marginal emission
to the grid the same amount of electricity                       Reducing energy use in existing build-                            rates, provided by ISO New England. See Appendix
that they consume each month, their                              ings can present additional challenges.                           A for a discussion of these calculations.
total electricity bill would be $8 – the cost
of the fixed monthly hook-up charge. As                          FUTURE COMMITMENTS
it is, they use an average of only 326 kWh                       The Lords will continue to gather data on
a month, and export 49 kWh. At a typical                         PV system performance, and post it on a

This case study reduces CO2 emissions equivalent to the following:
Avoiding the consumption of 6 barrels of oil per day

OR taking .47 vehicles off the road (which is equivalent to driving one vehicle 7,650 miles per year)

Assumptions: 1,093 lbs of CO2 per barrel of oil. Vehicles are average passenger cars (approximately 20 lbs CO2 per gallon of gasoline – 22.5 miles per gallon, averaging 16,000 miles per year)