"Islanders
tap geothermal energy - the heat beneath their feet"
From Martha's Vineyard Times, By Janet Hefler
- February 22, 2007 When it comes to alternative energy
choices, some Islanders look no further than the ground beneath
their feet. Geothermal energy provided by heat absorbed in the
earth from the sun offers them a free, clean, renewable energy
source for heating, cooling, and water heating in their homes
and businesses.
Two of the Island's biggest geothermal enthusiasts are Brian
Nelson and David Sprague, co-owners of Nelson Mechanical Design.
In addition to a geothermal system in Mr. Nelson's Vineyard Haven
home, they designed and installed a combination geothermal and
solar energy system in a home in Edgartown and are working on
a geothermal system proposed for the Oyster Bar Restaurant in
Oak Bluffs.
"The sun will never send you a bill, and peak sun, unlike
peak oil reserves, is still billions of years away," Mr.
Nelson says with a smile. As he explains the basics of how a geothermal
system operates, it sounds too good to be true.
Read
the rest rest here on the Times web site... |
Brian
Nelson spoke to the Martha's Vineyard Commission
regarding installing a geothermal system for the proposed Oyster
Bar in Oak Bluffs:
Minutes
of the Meeting of the Martha's Vineyard Commission, March 15, 2007
(linked) page 6-7 of 12
Brian Nelson, mechanical engineer, described
the geothermal system.
• Commercial project code requires
air exchange, which dictates the kind of low energy system that
can be used, in this case geothermal.
• The geothermal
loop system ties into the noise issue; there are no outside condensers
and everything is water-cooled through basement equipment.
•
The system will pay for itself in five years.
• The system
is a totally self-contained system and will require no supplemental
heating and air-conditioning. .
• There is no combustion
and no use of fossil fuels.
• Preliminarily, he estimates
they will bore twenty-five 100-foot deep holes. It is a closed loop
system. Mass DEP determines, based on where the holes are dug, that
the system will make no aquifer contamination.
• The
building envelope is more 36% energy efficient than the Mass Energy
Code. The state building code sets a bottom line minimum requirement
on windows and insulation. 36% is actually very high arising out
of the extra insulation. 36% efficiency doesn’t include the
heating system.
• Copper is very high on the nobility
scale; copper very quickly develops a protective coat. However,
they are adding a sacrificial anode; the pipes will also have impressed
voltage
• The pipes could be replaced but, in forty years,
there have been no tubing failures. 163
• In terms of
solar there will be conduits to the roof and the building will be
solar ready, but they won’t be installing solar right away.
• The 100-foot holes will be 2” in diameter.
• A bobcat size machine on tracks would bore the holes at
a shallow diagonal angle. The
process is minimally invasive and would be done after the site is
cleared.
Peter Cabana commented that
the Commission is currently developing energy guidelines. He recommended
that the applicant check out a website that might give them tax
benefits. He asked whether extra holes would be drilled and whether
other materials are used for the pipes.
Brian
Nelson said that the system is not new; Swiss geothermals
are done within the foundation. He also said they could consider
drilling extra holes for the future.
|
The Atria Restaurant celebrated the start up of its solar water
heating system on Saturday, July 29th at 6 PM. This solar system
uses the Sun to heat all of the hot water necessary for Atria’s
kitchen and bathroom use – over 700 gallons a day.
Atria’s decision to become the first solar powered restaurant on
the Vineyard is a major step forward in the “greening” of the island’s
commercial buildings and represents a 4 ton reduction in carbon
dioxide emissions every year!
This system features six 4' x 10' Alternate Energy Technologies
solar collectors, two drainback reservoir tanks, 400 gallons of
hot water storage, and a digital control system to operate the equipment
and trend energy production. |
