Solar roof tiles (shingles)

To the majority the main reason why they won't install solar panels is that some can look well... ugly. Nobody wants to lose their curb appeal understandably BUT, you don't have to get panels. You can get solar roof tiles and they look just dandy!

What are they and how do they work? 

Solar shingles, also called photovoltaic shingles, are solar cells designed to look like conventional asphalt shingles. There are several varieties of solar shingles, including shingle-sized solid panels that take the place of a number of conventional shingles in a strip, semi-rigid designs containing several silicon solar cells that are sized more like conventional shingles, and newer systems using various thin film solar cell technologies that match conventional shingles both in size and flexibility. Solar shingles are manufactured by several companies by now.

Solar shingles are photovoltaic cells, capturing sunlight and transforming it into electricity. Most solar shingles are 12 by 86 inches (300 by 2,180 mm) and can be stapled directly to the roofing cloth. When applied they have a 5 by 86 inches (130 by 2,180 mm) strip of exposed surface. Different models of shingles have different mounting requirements. Some can be applied directly onto roofing felt intermixed with regular asphalt shingles while others may need special installation.

Aren't they just dandy?!  There are all sorts of shapes and sizes that admittedly do aesthetically dance on the eyes more so than the panels!

Downside?

So it is a no-brainer then; fit solar tiles instead of panels unless you want to make a statement to your neighbours with your solar panels. Well – as is often the case – it is not as simple as that. The main issue is cost or, more to the point, return on investment. Solar tiles are more expensive – often double the price – and less efficient – typically 10 – 20% less than than solar panels. And as solar PV systems are being presented as an excellent investment with the Feed in Tariffs this will have an impact on their popularity and applicability.

Solar tiles still may have a part to play in the sustainable design of our buildings however. For those that view the appearance of their roof as paramount or for whom cost is not a concern may still want to make the extra investment. Also with new build homes, it may be practical to install solar tiles instead of conventional roof tiles which will offset some of the cost and look great; particularly if they cover the entire roof pitch.

I apologise for the poor quality of this blog post. It was copied from our current, new and improved blog that is here. It is updated daily and more often than not features solar panel news. I know there are still a few stragglers reading this blog and I thank you but, if you want it recently and updated then Home Improvement Blog will be right up your street! However if you are afraid of change then  I will try to maintain this blog to the best of my ability although it will be irregular and late, I apologise in advance!

I bid you adieu my dear Sirs and Madams!

Solar Windows Power Your Home?

A house window that doubles as a solar panel could be on the horizon, thanks to recent quantum-dot work. Scientists have demonstrated that superior light-emitting properties of quantum dots can be applied in solar energy by helping more efficiently harvest sunlight. Clever clogs.

Quantum dot LSC devices under ultraviolet illumination.

A house window that doubles as a solar panel could be on the horizon, thanks to recent quantum-dot work by Los Alamos National Laboratory researchers in collaboration with scientists from University of Milano-Bicocca (UNIMIB), Italy. Their project demonstrates that superior light-emitting properties of quantum dots can be applied in solar energy by helping more efficiently harvest sunlight.
"The key accomplishment is the demonstration of large-area luminescent solar concentrators that use a new generation of specially engineered quantum dots," said lead researcher Victor Klimov of the Centre for Advanced Solar Photophysics (CASP) at Los Alamos.Quantum dots are ultra-small bits of semiconductor matter that can be synthesized with nearly atomic precision via modern methods of colloidal chemistry. Their emission color can be tuned by simply varying their dimensions. Color tunability is combined with high emission efficiencies approaching 100 percent. These properties have recently become the basis of a new technology -- quantum dot displays -- employed, for example, in the newest generation of the Kindle Fire ™ e-reader.

Light-harvesting antennas

A luminescent solar concentrator (LSC) is a photon management device, representing a slab of transparent material that contains highly efficient emitters such as dye molecules or quantum dots. Sunlight absorbed in the slab is re-radiated at longer wavelengths and guided towards the slab edge equipped with a solar cell.Klimov explained, "The LSC serves as a light-harvesting antenna which concentrates solar radiation collected from a large area onto a much smaller solar cell, and this increases its power output.""LSCs are especially attractive because in addition to gains in efficiency, they can enable new interesting concepts such as photovoltaic windows that can transform house facades into large-area energy generation units," said Sergio Brovelli, who worked at Los Alamos until 2012 and is now a faculty member at UNIMIB.Because of highly efficient, color-tunable emission and solution processability, quantum dots are attractive materials for use in inexpensive, large-area LSCs. One challenge, however, is an overlap between emission and absorption bands in the dots, which leads to significant light losses due to the dots re-absorbing some of the light they produce.

"Giant" but still tiny, engineered dots

To overcome this problem the Los Alamos and UNIMIB researchers have developed LSCs based on quantum dots with artificially induced large separation between emission and absorption bands (called a large Stokes shift).These "Stokes-shift" engineered quantum dots represent cadmium selenide/cadmium sulfide (CdSe/CdS) structures in which light absorption is dominated by an ultra-thick outer shell of CdS, while emission occurs from the inner core of a narrower-gap CdSe. The separation of light-absorption and light-emission functions between the two different parts of the nanostructure results in a large spectral shift of emission with respect to absorption, which greatly reduces losses to re-absorption.

Concept of a Solar Window

To implement this concept, Los Alamos researchers created a series of thick-shell (so-called "giant") CdSe/CdS quantum dots, which were incorporated by their Italian partners into large slabs (sized in tens of centimeters) of polymethylmethacrylate (PMMA). While being large by quantum dot standards, the active particles are still tiny -- only about hundred angstroms across. For comparison, a human hair is about 500,000 angstroms wide."A key to the success of this project was the use of a modified industrial method of cell-casting, we developed at UNIMIB Materials Science Department" said Francesco Meinardi, professor of Physics at UNIMIB.
Despite their high transparency, the fabricated structures showed significant enhancement of solar flux with the concentration factor of more than four. These exciting results indicate that "Stokes-shift-engineered" quantum dots represent a promising materials platform. It may enable the creation of solution processable large-area LSCs with independently tunable emission and absorption spectra.
Sadly this all still just an idea and won't be in the mainstream market for a few more years. The idea though is  revolutionary. You could plug in your appliances into your WINDOW. Ideal for Kitchen windows, plug in your kettle and make a lovely cuppa powered by the sun, bliss. For more information on the Solar Window click here. Also there are many different companies trying to get their own spin on the Solar Window e.g. New Energy claim they are making a Solar Window that can out perform any commercial Solar Panel by 10 fold. Clearly in the foreseeable future not only will we see Solar Windows hitting the market but a whole range of them specially designed in their own unique ways!

Spectroscopic measurements indicated virtually no losses to re-absorption on distances of tens of centimetres  Further, tests using simulated solar radiation demonstrated high photon harvesting efficiencies of approximately 10% per absorbed photon achievable in nearly transparent samples, perfectly suited for utilization as photovoltaic windows.

I apologise for the poor quality of this blog post. It was copied from our current, new and improved blog that is here. It is updated daily and more often than not features solar panel news. I know there are still a few stragglers reading this blog and I thank you but, if you want it recently and updated then Home Improvement Blog will be right up your street! However if you are afraid of change then  I will endevour to maintain this blog to the best of my ability although it will be irregular and late, I apologise in advance!

I bid you adieu my dear Sirs and Madams!