Great Oak Common House Solar Hot Water Heater Proposal Summary
Background
We would like to install a 2 collector Solar Water Heater system
in and on the Great Oak Common House to provide a renewable
source of energy to heat water for the Common House.
The proposed system has been approved for rebate under the
"Michigan Solar Domestic Hot Water Rebate" program. Details of
the program are found at http://www.urbanoptions.org/. The
rebate program obligates us to have the system installed and
tested within the 90 days of approval. The approval was given on
Jun 27, 2005, so the system must be installed by September 27,
2005. The installers with the winning bid are extremely busy and
in addition to having to schedule the installation well in
advance (2 weeks at least at this point), they will take several
days to finish the installation, depending on the weather, so
deciding on this proposal is time-critical.
The proposed system to be installed is described at http://www.btfsolar.com/specifications.htm
and will be similar to the smaller systems installed on Units 24 and
11. Here is an artist's conception of the installed
collectors courtesy of Ted Chesky and a close up of an installed
collector:
Proposal
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The Solar Hot Water system will cost $6540 as per the bid. Once
installed, we will get a rebate check from the state within 6-8
weeks for $2800.
-
We have to devote the corner of the exercise room which
currently has a stack of tectum, to a heat-exchanger tank that
will be approximately 2 feet in diameter and 6 feet high
-
The payback time on this 2 collector system is estimated to be
26 years at the current price of Natural Gas. Based on the
current highest options pricing of Natural Gas (through
early 2006), the payback time could be as low as 16 years.
-
The funding for this installation will be via an "investment" in
the project by individual households. The investors will be paid
a dividend periodically (the detailed funding proposal suggests
every 2 months as that is the DTE billing period). The dividend
will be proportional to the investment. The dividend monies will
be equal to the measured energy that the Solar Hot
Water system produces, which would be equal to the amount of
Natural Gas saved in heating water, multiplied by the prevailing
cost of Natural Gas (as per the DTE bill).
NB. this funding model ensures that the community will
never pay more for heating water than if it was done
exclusively through Natural Gas supplied by DTE as is the case
now.
-
The operation and maintenance of the system should be minimal
over its lifetime and any labor and costs associated with those
will be borne by the investors until the system is paid off, at
which time the community becomes the maintainer/owner. Repairs
requried due to possible damage to the CH by the system (say due
to leaking pipes) beyond those performed during the 2-year
warranty period will be the community's responsbility.
Pros
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contributes a sustainable energy installation to the community, state and
world, reducing demand on expensive, polluting and unsustainable resources
-
innovative funding model that allows households to participate as
little or as much as they like, and allows for future participation
-
when the system is "paid back" the community owns the system outright
and gets renewable, non-polluting energy for free from then on!
-
we already have several households that have pledged money toward the
system
-
shows the commitment to sustainability the community wishes to embrace -- quote from an investing household:
For me, one of the positives about it (solar collectors) being very
visible is that for whatever reason, our community was not built as
"smartly" as it could have been, and our buildings don't seem to
cooperate with the sun much at all. I like the idea of having quite
visible examples of trying to make our situation more environmentally
friendly. I want our kids to see this stuff every day. I want *us*
to see this every day.
-
serves as an experiment and hopefully showcases the role such
alternative energy installations can play year-round in energy-poor
Michigan
-
will encourage other Great Oak and Ann Arbor cohousing units to
consider similar systems
-
takes advantage of a limited-time statewide initiative and incentive program
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This funding model can be thought of as a "buying cooperative" or "The
Great Oak Energy company" -- expressing the power of collective
buying/producing
-
The funding model ties the consumers and producers together such that the results are
clear in economic terms
Cons
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possibly aesthetically lacking
-
will require space (albeit currently badly used) in the
already-cramped exercise room
-
introduction of sealed holes in the roof decrease its integrity, though the
included, proper, warrantied sealing should mitigate any problems
-
No Michigan references yet -- might be worth waiting a year to see how
other systems installed at GO units perform, but that might mean
foregoing a rare and possibly unique state rebate.
-
The payback period could exceed the length of time an investor lives
at GO
-
the investor would be responsible for finding someone to buy their
shares if they are no longer interested
-
the payback period is dependent on the performance of the system which
is based on many factors beyond local control like the weather and the
price of natural gas
-
the funding model requires a "fund" manager to calculate the dividends
every 2 months and requires the member bookkeeper to add another
lineitem for some subset of households (much like the prepaid CH loans
but more complex because the lineitem amount will change each
time).
A detailed technical summary of the project is available.
A detailed email about the proposed funding option is available at
http://gocoho.org/pipermail/talk_gocoho.org/2005-July/001275.html.
R.P. Aditya
Last modified: Wed Aug 3 19:38:38 GMT 2005