Solar Feed In Tariff Website

Cambridge based solar technology company Polysolar has developed a hi-tech photovoltaic glass which could be used at next year’s Olympic Games in London and also the 2022 FIFA World Cup in Qatar. Polysolar’s transparent PV glass has been designed for use by architects in windows, cladding and glass structures as a way of generating green energy. The glass is already in use in other countries and is able to generate 100w of energy from each pane of glass making it an effective way of generating clean energy from wall and roof space.

Explaining the idea behind the glass, Hamish Watson the founder of Polysolar said,

“Our product is different from any other solar panel on the market, because it can be used as a building material, making it a highly cost effective integral part of the building. Unlike traditional solar cells, which need to be southward facing, the glass can be positioned anywhere, so is more flexible for large scale architectural and engineering projects and hence it generates a higher yield.”

Importantly, Polysolar’s glass has received MCS certification for the UK feed-in tariff. This means that where installed, landlords will be able to generate revenue from the energy which the panes generate which is used or fed back into the national grid. The Ploysolar product will also have the attraction that where installed, property owners will see massive reductions in their electricity bills. Aside from the obvious financial benefits, Hamish Watson is well aware that the green credentials of solar pv technology will be very welcome by event organising committees.

“Our PV glass has generated a lot of interest and we are in discussions to install it at the 2012 Olympic village, where it could be used to help generate power for information displays across the site. We have also had early discussions with the organisers of the 2022 World Cup and the developers of London’s Walkie Talkie building – both projects are obviously quite exciting for our company.”

Tags: Polysolar, solar energy, Solar Feed In Tariff, solar glass, solar panels, solar PV, solar technology

Monitoring

How do I know if my PV system is working properly? This is a very good question and something that many customers of solar energy systems wonder. The answer is to spend some time and perhaps some money in monitoring the performance of your system over an extended period of time.

Perhaps the first point to mention is that a good installer should do this for you. They should care deeply whether or not their installations perform as well as they will have predicted. Before choosing your installer try to determine what they offer in terms of after sales support and care.

If you like to take matters into your own hands there are a number of ways to monitor your system. If you are not inclined to pay extra for monitoring hardware, the simplest solution is to use information from the displays of the generation meter or the inverter (or both). Both these instruments will be present in all PV systems installed in the UK by a microgeneration certification scheme installer and will be able to tell you the number units of electricity generated since the system was put in. Get into the habit of checking this number at the end of each day, along with a record of what the weather was like – clear sky, partial cloud, heavily overcast etc…

Your installer will have provided you with an estimate of the annual energy production in kWh – in southern England this should be in the region of 850 kWh per kWp). This means that over the course of the year you should expect an average of two and a half kWh of energy each day for every kWp you have installed. This is heavily dependent on the weather of course. On a clear day you could expect 8 kWh, and on a very dark day as little as 0.2 kWh. After several days of checking you should be able to have an idea of whether your system is significantly under-performing.

Over time, your measurements will become more reliable. Each month of the year has an expected solar energy output. Ask your installer for a chart showing the average monthly variation of solar energy for your location. After one month you can compare the energy you got with what you would expect. Be warned however, monthly solar energy output can vary widely, some months can be particularly good or bad for solar compared to normal, so comparing with the average is not necessarily accurate. Still, you should be able to tell if you are getting 30% less energy than you should be.

Getting a more accurate picture of your system’s performance is challenging. For instance, if your system is underperforming by 10%, how do you prove this?

A good method is to compare it to a nearby reference system which is known to perform well, and compare daily production to that. This can be challenging to find however, especially in the UK where there are still very few PV installations.

Another technique is to try to determine if there is something wrong with your system. Your inverter should also tell you the DC voltage and current coming from your solar panels. Under a clear sky, you can check if these values are in line with what they should be from the datasheet. Whether the voltage or current is lower than expected can provide information on what might be wrong.

If your system is underperforming, it could well be because of shading. If shadows are passing across the solar panels during the course of the day that weren’t accounted for in the system design, then this can really contribute to underperformance. Try to get in a position where you can see the solar panels at different times of the day. Any shadows on the module during the middle of the day (when they should be producing the most energy) can be serious. Many systems will be shadowed in the morning or evening, but this is generally less severe. Make sure to also check for dirt or muck on the panels, even small markings can cause big performance losses for solar systems.

It is also worth looking out for long term degradation. Whilst rare, it has been known for systems to get significantly worse over time.

If you would like buy a monitoring solution yourself then the simplest product is a power meter. Examples are the ‘OWL’ meter or the ‘Wattson’ made by DIY Kyoto. These are both simple meters that can easily be installed by clipping a sensor onto the AC output cable of your inverter. What’s useful is that the data can be transmitted wirelessly and viewed in real time and even stored to show you how energy production varies over the course of the day.

Depending on your installer, many will offer to monitor your system for you. This can be advantageous since they will have access to data from a large number of systems on which to benchmark performance. Make sure to ask them exactly how they plan to do this however.

On the upside, most systems should perform fine and are unlikely to go wrong but when you’re investing such a large amount of money in a PV system, its nice to know how to check its working.

Tags: DIY Kyoto, Inverter, Monitoring solar p.v, OWL meter, p.v, P.V performance, solar technology