Dow's solar shingles are available for homeowners

Finally this month – October 2011 – Dow Corning’s Powerhouse Solar Shingles are finally available for homeowners.  The company’s catch phrase is:

“Our Solar Shingles aren’t on the roof, they are the roof.”

If your home improvement list includes re-shingling the roof, perhaps you should consider Dow’s solar shingles to generate clean and green renewable energy.  The solar shingles will be available this month in Colorado, and then rolled out to California and other targeted states throughout the coming year.  Constructed with glass-free, thin-film, building-integrated photovoltaics, the solar shingles are like conventional roofing shingles in almost every regard.

Dow’s solar shingles are durable and simple to install and use.  While there are a number of benefits, the only drawback is that consumers are still awaiting a final estimate on solar shingles’ price.  However, Dow Solar Vice President Jane Palmieri commented that their solar shingle systems may cost cost up to 15 percent less than conventional solar panel arrays.

With federal, state and local solar tax credits, solar shingle projects are probably more affordable than you’d think.  Ranging from $8,000-15,000, these systems can generate half (or more) of a home’s power requirements.  Not only that, but if you pay for regular roofing materials, as well as solar panels, you’ll invest thousands more than with Dow’s solar shingles.  The specialized shingles last as long – if not longer- than regular asphalt shingles.

What do you think about Dow’s solar shingles?  Will they change your mind about switching to solar power?

Solar shingles: building integrated photovoltaics

That’s where BIPV comes into play.  With solar panels that are “built into” a structure, such as solar shingles, you can enjoy a streamlined appearance that are practically invisible.  These rooftop installations lie flat against the top of a home or building and can last as long as ordinary roofing materials, but they do not require roof penetrations to install and also are lightweight.

Building integrated photovoltaics are favored by many property owners because they are either invisible, or difficult to see from obscure angles, particularly where the south-facing facade of the home is also the front/street side.

Solar shingles look exactly like ordinary roofing shingles in their shape and size, but they are created with photovoltaic (PV) materials so that they become mini solar panels on your roof.

Even though solar shingles are wonderful from an appearance standpoint, there are a few downsides: (1) price – they are more expensive than regular solar panels; (2) they are not as efficient than PV panels, which means you need more (adding to the cost for the product itself and installation); and (3) they only come in black – so, if your roof is red tile, brown or any other color, solar shingles will not blend in quite as well as you might hope.

In summary, before you go with BIPV installations such as solar shingles, do some research and determine the pros and cons from your own personal standpoint.  Hopefully, you can find a way to go solar!

Building Integrated Photovoltaics

As shown above, building integrated photovoltaics is the practice of “building in,” if you will, solar panels or solar cells to a completed structure.  The solar panels become part of the building design.  Thus, instead of using clunky, thick solar panels on your rooftop, BIPV may include “peel and stick” solar panels, solar windows, solar paint and solar shingles.

When you go with building integrated photovoltaics, you not only improve the appearance of your building, but you can also save money on both materials and installations.

There are several primary types of BIVP:

1.  Solar Roofing

Solar roofing using BIPV technology consists primarily of solar shingles or solar tiles, but can also incorporate peel and stick solar panels (also known as solar laminate panels). The thin profile is aesthetically pleasing and often virtually invisible, as the roofing material is literally incorporated into the roof itself.

If you own a metal or flat roof, solar laminate panels may be for you.  They are easy to install and you can have solar power within a hour!

2.  Solar Paint

Solar paint has great promise. It incorporates dye-sensitized solar cells under a layer of electrolyte or titanium dioxide and is painted onto sheets of metal.  When sunlight hits the solar cells, it excites molecules that function as light absorbers. Electrons are released into the titanium layer of the paint which acts as a circuit. Electrons move into the dye, generating electricity.

Compared to regular PV solar cells, solar paint can absorb sunlight across the spectrum, including low radiation frequencies.  And, it is more cost-effective to construct a building with components that incorporate solar paint than later installing solar panels.

Solar windows

3. Solar Windows

Miniature PV cell technology can also be used on windows coated with semi-transparent solar cells. Solar windows have a solar film rolled onto a glass pane to reduce UV light and glare, and to provide shading for the interior of a building (consider west-facing windows late in the afternoon). The film has an insulating effect – reducing heat during the hottest part of the day, and preventing its escape when it cools down. In other words, while you are capturing solar energy and converting it to free electricity, you can also be lowering your heating and A/C costs.

There are a variety of hues of solar film for windows, and the options range from nearly transparent to heavy shade, depending on your desires.  The technology has also been applied to sun roofs in vehicles – the 2010 Toyota Prius is an excellent example.

Solar panels that double as skylights? Really!

We love the idea of building integrated photovoltaics (BIPV), yet beyond solar shingles or solar windows, what can you really do to integrate solar electricity generating building materials into your home?

Consider these solar panels that double as skylights, developed by Architect Gerald Choi.  Personally, Choi needed to update some skylights in his home, but the estimate shocked him at over $50,000.

Spurred on by necessity, Choi invented combination bi-facial skylight PV system.  These skylights/solar panels allow sunlight/moonlight to flow in, while solar power is generated.  Not only that, but the system is practically hidden from view!

When working on his revolutionary solar panels/skylights, Choi discovered that he could slash the $26,000 retail cost for the materials to only $13,000 due to solar rebates and government tax credits.  And, since installing the BIPV system, Choi’s utility bills have dropped to $18 a month.  The solar panels that double as skylights produce enough energy that Choi can take advantage of net metering to sell back extra electricity to the local grid.

Jerrod Schreck, president of Hoku Solar and the man that helped design Choi’s system, comments that we will see more BIPV developments in the near future:

“I see the time coming when PV systems are architecturally integrated [into the structure]. We’re going to be developing PV systems working with architects. When they start drawing new buildings, they’ll already be talking about the energy load.”

This is the time at which we are seeing convergence of design with economics.  Sleek, more invisible means of generating clean solar power will become more popular and affordable as we move away from our dirty, fossil fuel habits.

Solar windows to be installed at Willis Tower

Recently, Pythagoras Solar, announced that it has been chosen to collaborate on a pilot project to help Willis Tower realize its renewable energy and energy efficiency improvement goals.  South-facing windows on the skyscraper’s 56th floor will be transformed into solar windows that can generate over 2 megawatts (MW) of solar energy.

John Huston, Executive VP of American Landmark Properties which co-owns Willis Tower commented:

“We are excited to launch this pilot with Pythagoras Solar’s leading-edge solar window solutions as a test for not only the energy savings that can be achieved, but the potential they represent to actually generate power through the sun.”

Just think of the potential if all skyscrapers in the world also installed solar windows, following the lead of Willis Tower!  Its now possible, given solar technology like that of Pythagoras Solar, which is the first company to offer a fully integrated photovoltaic glass unit (PVGU) that addresses the need for simultaneous benefits of energy efficiency and high power density, while also offering architectural design benefits to increase real estate value and advance Net Zero Energy Buildings (NZB).

Concentrated Solar Power becomes Building Integrated

Concentrated solar power is a technology for generating utility scale solar power.  But Syracuse’s Center of Excellence in Environmental and Energy Systems (SyracuseCoE) is showing that it can also be building integrated and used on a smaller, direct generation scale.

At SyracuseCo, the building itself is a LEED-platinum-certified, 55,000 square-foot building that serves as a testing ground for renewable energy and efficiency technologies.  But head to the south wall of the building and there, you will find a concentrated solar facade (pictured above), that serves multiple functions.

This is building integrated photovoltaics in a whole new light!  The 8×8 foot facade includes clear pyramid heliotropic lenses that concentrate sunlight on high-efficiency PV solar cells.  Solar energy is generated at an efficient rate, and any additional power not needed for electricity is used to heat the building and water.  Not only that, but the clear panels add natural light for the interior, which reduces lighting requirements.

The facade was designed by the Center for Architecture Science and Ecology and HeliOptix has marketing rights.

See-through solar film for windows

One of the most promising new technologies in building-integrated photovoltaics may be see-through solar film for windows.

New Energy Technologies announced yesterday that its researchers developed a new, patent-pending process for spray on solar cells.  When applied to glass, the innovation transforms it into a “Solarwindow,” providing a unique way to tap into solar energy and save costs.

The president and CEO of New Energy Technologies commented:

“The ability to spray solar coatings directly onto glass follows on the heels of our recent breakthrough which replaced visibility-blocking metal with environmentally-friendly see-thru compounds, and marks an important advance in the development of our see-thru glass windows capable of generating electricity.”

Can you imagine generating solar electricity with the windows on your home or building?  Dye-sensitized solar cells make it happen!

Solar Windows coming to a building near you soon!

The SolarWindow developed by New Energy Technologies would be available for use by the nearly 5 million commercial buildings and 80 million single family homes in America.  The company states that solar coatings would be sprayed directly onto its SolarWindow and would not block views or sunlight from passing through, unlike other solar film.

New Energy’s researchers developed a way to eliminate metal from its spray-on solar film technology.  When present, metal is opaque, blocks visibility and prevents light from passing through the glass.  It is not easy to remove metal from solar film, however, given that it acts as the negative “polar contact,” which aids in collecting the generated electricity.

At New Energy, scientists replaced the metal negative polar contact with transparent, more environmentally-friendly compounds.

The spray-on solar cells used by New Energy are ultra small and ultra-thin: only 1/1000th of the thickness of a human hair.  When combined with the transparent negative polar contact materials, the result is a see-through photovoltaic application.

Transparency is the key to effective, marketable solar windows!  With the new technology, commercial and residential property owners can soon enjoy relatively low-cost, yet effective solar electricity generation.

Building integrated photovoltaics allow use of solar energy without solar panels

Have you dreamed about solar energy to power your home?  Do you want to start generating free solar power and enjoy reduced electricity bills?  Those large solar panels that are becoming commonplace on rooftops are not your only option.  You can indeed have home solar energy without solar panels.

That’s right.  Building-integrated photovoltaics is the fancy term for solar roof shingles or solar roof tiles.  As described by Alfonso Velosa III, co-author of a coming report on the market for the new field, in a recent interview for the New York Times:

“The new materials are part of the building itself, not an addition, and they are taking photovoltaics to the next level — an aesthetic one.”

Whether you are considering solar panels or solar shingles, the process of converting light to energy is the same:

Solar roof tiles can blend into any type of roofing surface/materials

As a land use attorney, my hope is that building codes will soon be revised to require – or at least give a preference to – new construction to include either solar panels or solar roof shingles.  Perhaps the Uniform Building Code Council will take the lead?

But I digress….

No matter what style of roofing you have, you can find solar tiles/shingles in colors and shapes that blend in.  From rosy-hued terra cotta tiles to salty, wind-worn gray shingles on oceanside cottages, solar shingles become part of the roofing materials, rather than an obtrusive addition.  With federal and state incentives offered for renewable energy improvements, plus the added value your property will enjoy ($20 for every $1 annually saved on energy bills), this is a perfect time to invest.

According to the New York Times:

SRS Energy of Philadelphia is making curved solar roofing tiles designed to blend in with Southern California’s traditional clay tiles, said Martin R. Low, the chief executive of SRS. A solar tile system that met half the power needs of a typical California home would cost roughly $20,000 to install after rebates, he estimated, or about 10 to 20 percent more than solar panels providing comparable power.

The building integrated photovoltaics market is not entirely new, or untested.  In European countries including Germany and France, the market is quickly growing due to subsidies and programs that pay people for generating solar electricity ad feeding it back into the grid.  On the “other side of the pond,” homeowners can recoup investments in 5-7 years, compared to the 10-20 years it may take here in the U.S.

I do believe the United States will catch on.  Demand will fuel the market here, and we do not expect solar subsidies or tax incentives to disappear anytime soon.  In fact, when solar looks this good, we could even see new programs to help further defray the costs and encourage a conversion to solar power.