Solar Energy is a great way to get us started on the road to becoming a Renewable Energy Island and help us achieve greater energy independence. Generating power and making hot water on island homes and businesses reduces our contribution to Climate Change, particularly when combined with energy efficiency efforts. Energy generated locally is more efficient because there is less transmission loss.
Excerpts from the Island Energy (and Waste) Plan
Island Energy Plan Renewable Energy Goal
Maximize opportunities to generate energy from renewable sources to meet the island's energy needs.
Currently, less than 1% of the island's energy is supplied from renewable sources. The Energy Plan developed in 2005 suggests that wind and solar are the best ways to generate renewable energy for the island. Our almost island-wide wind resource gives us a greater opportunity than many communities to generate renewable energy.
Solar electric (photovoltaic) and solar thermal (hot water) systems are proven technologies that generate energy year-round but have varying seasonal output, with greatest generation in the summer when our energy demands are highest. Solar pool heating has the quickest payback of all active solar technologies and would significantly lower the energy impact of island pools.
As of December 2006, the Vineyard had 90 solar electric systems, a total of 150 kilowatts. Most systems are grid-tied, with some of the earliest ones being stand-alone systems, particularly those on Cape Pogue. In addition we had 72 known solar hot water systems, many of which date back to the late 1970's, for a total of 6746 square feet of collectors. Of the 72, three are solar pool heating systems, installed in 2005-6.
With present photovoltaic technology, we can make 17 kilowatt-hours (kWh) of electricity/square foot/per year. Supplying a typical Island household requires about 400 sq ft of collector at current average consumption of 6000-7200 kWh/year. The 90 systems we have today will generate approximately 175,000 kWh during 2007 – about 0.1% of our needs. To supply all our electric energy would require about a square mile of collector (one third of a square mile plus spacing between panels to eliminate shading). Solar electric arrays are well suited to installations at individual sites to take advantage of existing roofs, existing development, and thereby eliminate transmission losses.
Sun-tempering (passive solar heating) is a cost-effective approach to provide heating for buildings. Large, south-facing windows are the primary component. When installed in super-insulated buildings, passive solar techniques can provide roughly half of the required heat, and do so without using electricity.
By 2015, 5% of the island's electricity will be generated from solar or wind; 30% of the Island’s heating to be produced from renewables.
By 2025, 25% of the island's electricity is generated on the island or directly offshore from renewable sources, and 75% of the Island’s heating to be from renewable sources.
By 2050, the island produces 65% of our transportation energy and, with excess renewable electricity generation sold off-Island, we are offsetting 90% of our remaining carbon emissions, making us almost carbon-neutral.
OBJECTIVE 2: Develop capacity to encourage and support the development and installation of renewable energy generation.
OBJECTIVE 3: Maximize potential for On-Site generation of energy
Generating energy on-site is an effective strategy as it eliminates transmission losses and reduces the size of the generation facility, which can reduce concerns about visibility. All sites should be thought of as potential energy generation locations. Solar electric and wind systems can generate power for the island year-round whether or not the buildings they are associated with are occupied. Solar hot water is particularly beneficial for buildings that are occupied year-round and for sites with high hot water demand.
3.1 Use mapping and other technologies to identify sites with advantageous access to renewable energy sources, including existing, un-shaded, south-facing roofs or ground area.
3.3 Require that construction or renovation of a pool that is to be heated must be accompanied by solar, geothermal or other on-site renewable heating source adequate to meet the pool's heating needs, and that all pools and hot tubs have insulated covers. Devise program to supplement or retrofit existing pools and hot tubs.
3.4 Supplement existing water heating systems – target those employing electric water heaters – with solar thermal systems.
3.5 Require solar hot water systems at all year-around housing when there is solar access and on any buildings that will be using large amounts of hot water (e.g. the YMCA, hotels or restaurants).
3.6 Research and implement ways to provide supplemental heat to farm greenhouses with solar thermal technologies.
3.7 Except when historic aspects or other site considerations are of greater significance, require all new developments and construction projects to:
• Orient buildings to maximize solar gain, solar energy generation and day-lighting opportunities
• Optimize winter heat gain by having fewer trees to the south
• Be designed for future solar energy with uninterrupted south-facing roof expanses and orientation optimally within 15 degrees of true south,
• Position buildings so as not to shade each other
• Prepare buildings to enable installation of solar hot water and solar electric systems in the future if site has south-facing roof or ground area.
3.8 Add to or upgrade town bylaws to encourage solar and wind generation.
3.9 Provide information on available equipment, funding options, zoning and interconnection issues for all technologies.
3.10 Develop incentive programs to encourage on-site energy generation property tax breaks, low interest loans, funding from Island Energy Fund and feed-in tariffs (once island utility company is established).