New Solar Panels Are Built Specifically For Slanted Rooftops

Scheuten Solar recently presented its Multisol Integra; an integrated PV-solution suited for almost any sloped roof. This PV in-roof installation system replaces the conventional tile covering; whether as a part of the roof or as covering of the entire roof.

This new solution seamlessly fits into contemporary market demands which ask for relatively small and flexible integration of PV modules. Multisol Integra will be first introduced in France, where the system qualifies for the feed-in tariff available for building integrated PV solutions.

Multisol Integra is based on the Solrif system by Ernst Schweizer AG consisting of an aluminum construction designed for simple and fast installation. Since the market launch of the Solrif™ system in 1999, it has been used extensively in a variety of installations in tens of MWp.

www.scheuten.com

Yosemite Nat. Park Receives $4.4 million Solar Project

Beginning in June, Yosemite National Park will install a large-scale solar panel project at El Portal that will accommodate a 539-kilowatt photovoltaic generation system with $4.4 million received under the American Recovery and Reinvestment Act.

Once built, this will be the largest grid-connected photovoltaic system in the National Park System.  Upon completion of the project, the park will double the electricity produced through renewable energy for the Pacific West Region of the National Park Service, which consists of 58 sites.

The rooftop and shade structure mounted solar panels, to be installed beginning this summer at the El Portal Maintenance Complex, are expected to generate approximately 800,000 kilowatt hours of electricity annually.  This will result in almost a 12 percent savings on electricity purchased off the grid.

El Portal, the park’s administrative center, was chosen as the location for the solar panels based on the high amount of direct sunlight the site receives. This $4.4 million project, funded by the American Recovery and Reinvestment Act, is a design-build contract and was awarded to Paragon Industrial Applications of Atascadero, California.

The solar panels will be installed on the roofs of existing buildings and on newly constructed shade structures in which government vehicles will be parked under.  At 13 cents per kilowatt hour, the park is projecting a savings of up to $104,000 per year.  The construction is slated to begin in June 2010.

www.nps.gov/yose

Is The Future For Solar In Deserts Or On Rooftops?

A recent study by David Anthony says that solar energy, despite all of the effort to increase its usage, still only accounts for less than one percent of the energy we consume.   The amount of solar energy that reaches the Earth’s surface every hour is greater than mankind’s total demand for energy in a whole year. The total energy stored in the world’s supply of fossil fuels is equal to just twenty days of solar energy.  By any measure, the sun is a powerful and virtually limitless source of energy and it is imperative that we capitalize on this clean energy source by increasing our use of solar energy and reducing our reliance on fossil fuels.

How do we begin to capitalize on such a rich source of energy?  Both distributed and utility-scale solar energy projects are vital to accommodate the world’s growing energy needs as they are both suited to harness the extraordinary power of the sun.   The underlying technology used by utility and distributed solar is different and understandably, each has its own proponents and detractors.  For the most part,utility-scale solar projects use solar collectors to generate enough heat to power a steam turbine that in turn generates electrons.  Distributed solar energy derives primarily from the use of photovoltaic panels that capture photons and convert them into electrons. Distributed PV efficiency is improving all the time.   Currently, there is a conversion efficiency of approximately 17% for crystalline silicon panels and 10% for thin film panels — a dramatic improvement from only a few years ago.

In California alone, there are plans for 35 utility-scale projects that would generate approximately 12,000 Megawatts (MW) of energy annually — an amount of energy comparable to the combined power of ten nuclear power plants.  The Mojave Solar Projectand the Genesis Solar Energy Project, both located in southern California, are two of the largest projects under consideration and are each aiming to generate 250M watts of energy. These projects are expensive, however, in terms of both dollars and natural resources required. The federal government has promised to help reduce the financial cost by allocating a portion of the stimulus plan for this purpose.  Companies that have their plants ready to be opened by the end of this year will receive a portion of the $67 billion of federal money that has been set aside for renewable energy projects (including loan guarantees and grant programs).

Despite these incentives, it is risky to undertake a large-scale enterprise like utility-scale solar power in an uncertain economic climate, as financial institutions are reluctant to be involved in billion-dollar projects.   Another issue is the fact that such solar ‘farms’ require huge tracts of land. The Bureau of Land Management (BLM) has been tasked with finding 24 tracts of public land of three square miles each with good solar exposure, favorable slopes, road and transmission line availability. Additionally, the land set aside for utility-scale solar farms must not disturb native wildlife or endangered species such as the desert tortoise, the desert bighorn sheep, and others. The wildlife issue has proved to be a contentious one. Projects in California have been halted due to the threat caused to endangered species resulting in a backlog of 158 commercial projects with which the BLM is currently contending.

Another challenging issue for utility-scale solar projects is the use of water.   Combined, the Genesis and Mojave projects would use 1.24 billion gallons of water per year due to the wet cooling systems involved.   One alternative to wet cooling systems, dry cooling, uses 90% less water, but can only handle the full cooling load up to temperatures of 85˚-90˚F.   As a result, dry cooling in deserts is not cost efficient.   Just as challenging is the fact that to date, there are no affordable storage solutions for utility-scale solar projects.   Without the means to capture and store excess electricity produced by solar farms, an enormous inefficiency is created.

An alternative to utility-scale projects is the use of distributed solar energy.  There are various types of renewable power technologies in use, but sub-utility scale power photovoltaics (PV’s) account for 98% of the distributed solar energy market.  Unlike utility-scale projects, distributed energy is solar power on a small scale and entails the installation of solar panels on the roofs of buildings.  Toward the end of 2009, the California Public Utilities Commission unanimously voted for the Southern California Edison’s Plan.  This plan recommended scattering solar panels on rooftops all over the region in an effort to create 500MW of energy.  Like utility-scale, the plan benefited from the 30% federal tax credit for renewable energy projects.

Distributed solar power does not involve the legal red tape, the large tracts of land, or the vast quantities of water that utility-scale projects require, and has the ability to generate enough energy for homes, schools and hospitals.   Installation is easily addressed and solar panels can last for up to 30 years if well maintained.   The price of solar panels has dropped dramatically to approximately $2.40 per watt (price depending on scale of order) for silicon panels and is likely to drop even further in 2011.   Furthermore, unlike utility-scale projects, distributed solar projects such as the Southern California Edison’s Plan spread capacity evenly, distributing benefits and drawbacks.   If a utility-scale project “crashes,” it affects a huge area.  With distributed energy, only individual units are affected in the case of a power outage.

In many locations and in certain circumstances, distributed solar projects are less expensive than utility-scale solar projects because of the avoidance of both new transmission lines and line losses — the latter of which typically accounts for approximately 7% of the power shipped over transmission systems. The costs associated with utility-scale solar projects are often not included in the side-by-side economic comparison made between the two forms of solar power development.  An additional benefit of distributed solar is its ability, when developed in clusters (i.e., local micro-grids), to alleviate the need to upgrade distribution substations and add local peaking plant capacity.

As mentioned, distributed solar plans have their detractors. Solar certainly is not the cheapest source of electricity and is only effective in areas with a high percentage of sunshine.   More than 50 million Americans live in Community Associations where we might expect to see efficient adoption of distributed solar plans. But these locations commonly have policies limiting the use solar equipment due to height restrictions or other specifications regarding roofing materials.

Utility-scale projects may have the capacity to generate enormous amounts of energy but they represent a huge financial risk, irretrievable waste of resources, and threats to endangered species, all of which are problems that may take years to solve.  On the other hand, distributed solar power entails a fraction of the risk posed by utility-scale projects and is poised to capitalize on the vast opportunity offered by 140 million residential rooftops in the U.S. alone, not including all of the commercial rooftops available for PV installation. Distributed energy is certainly the way forward in the field of solar energy use.

www.greentechmedia.com

Largest Rooftop Solar Project Will Be Built In Boston

Construction on the largest roof-solar project in Boston will begin this month.  Developed and designed by the consortium of Rivermoor Energy, Fischback & Moor Electrical Group, and Zapotec Energy, Inc., the 240-kilowatt project at Boston Water and Sewer Commission (BWSC) headquarters will connect to the NSTAR grid.

The complex project involves installing a 240-kilowatt solar photovoltaic system on the BWSC rooftop on Harrison Avenue in Boston.  Leveraging Massachusetts’ Solar Renewable Energy Credits, construction and installation of the $1.075 million project will take approximately three months and will create over 15 clean energy jobs for Massachusetts. When complete, the new solar energy system should produce 268,000 kilowatt hours of power annually, about 7 percent of the Commission’s current power usage, which is the equivalent of planting 1,000 trees a year.

www.rivermoorenergy.com

How effective is residential solar power?

The effectiveness of a solar power system for powering your home (or part of your home) depends upon a number of factors. For example:

• Electric or gas? In general, any appliance that uses electricity to power a heat element (for instance, an electric stove, an electric clothes dryer, or an electric water heater) is not very compatible with solar power.

To get the most from a solar panel system, the first thing you should do is switch out energy-inefficient electric appliances with more efficient gas or propane appliances.

Replace water heaters with tankless, gas-powered water heaters; replace electric range tops with gas ranges; and replace electric clothes dryer with a gas-powered clothes dryer.

• How well does your home regulate its temperature? Probably the largest category of energy usage in a home is heating and cooling. Air conditioners use an inconceivably huge amount of power, and central heat falls not far behind.

If you haven’t weatherized your home yet, take advantage of the current tax credits offered as part of the Recovery Act and make your home as energy efficient as possible. The more energy efficient your home, the more cost-effective solar power will be.

• What is the south side of your roof like? Solar panels are most effective at catching sunlight when they are located on a south-facing roof.

If you have a neighboring building that blocks sunlight to the south side of your roof, you may want to think twice before you make a large investment into a solar panel array.

If you have trees shading that side of your roof, you may want to cut them down or at least trim them before installing solar panels.

• Where do you live? Even if the south side of your roof is completely clear and free, there’s a big difference between the amount of sunlight a south-facing roof receives in San Diego, CA, compared to Nome, AK. You should check NASA’s helpful Surface Meteorology and Solar Energy website to see if your particular area receives enough annual sunlight to make solar power a viable option.

These are just a few of the many factors that determine the effectiveness of solar power. Remember, solar power requires a significant financial investment, so be sure to do your homework carefully to decide if solar power is the best alternative energy option for you.

About the Author

Shannon Bell writes for residentialsolarpanels.org a non commercial blog focused on her Photovoltaic experiences to help people understand how and why they should save energy starting investing in solar power. She writes on <a href=” http://www.residentialsolarpanels.org/ “>residential solar energy</a> to help people learn how to start save energy from the scratch and then apply those experience to the next level.