> Solar Power - the facts about setting up Solar Power - Page 2

Should I trade in my RECs?

Most countries now have RECs (Renewable Energy Certificates) or equivalent schemes. Basically it is a mechanism for attributing the cost of greenhouse gas emissions to be offset against a none or lesser greenhouse gas producing energy source - such as solar panels or wind power which produce renewable energy. The idea is that green house gas producers need to buy REC's to keep their net pollution below their allocated threshold. So if you sell all your REC's in effect, from the environments point of view, its a zero sum game (i.e. pollution generated balances against pollution stopped). So instead of making a net 'green' contribution to the environment you just keeping the status quo...

Also with this REC scheme there is a lot of what could be termed 'perfect market assumptions'; i.e. we know precisely what is an acceptable level of pollution and we know precisely how to 'value' that pollution against what offsets it.

Now if you do not trade in your REC's, what happens? Well for starters, the buyers of REC's will need to go elsewhere - so by you keeping those REC's you change the game from being zero sum to pollution negative (i.e. you have voted against allowing your green power to be offset against the pollution generated). Also by reducing the number of REC's in the market, supply and demand dictates that for the buyers the cost of those REC's are more likely to go up.. Of course by not trading in your REC's your initial cost will be much higher. Or look at this another way, the amount you paid after trading in your REC's is in effect a subsidy cost benefiting the pollution producer, i.e. its your 'sunk cost' to allow them to pollute!

Also in Australia there is now a multiplier scheme in place, i.e. 5x the normal number of REC's on a qualifying system - what this means is that for the same 'physical' amount of carbon reduction its having 5 times the offset effect in the market! So basically the REC market is getting flooded with cheap RECs, distorting the whole process for years to come... Which indicates two things: 1) how little people really understand whats going on with the REC marketplace, and 2) that the government has been 'hoodwinked' by big business into making polluting cheap for them.

At the moment bug business is busy doing what ever it can to buy up these cheap REC's; as with an increasing focus on green house gas emissions and the REC scheme being applied to more market sectors, the financial value of these REC's can only really go up in the longer term... REC's are completely tradable in a global market remember..

The other thing with REC's that is actually quite nasty, is that it allows the pollution producers to 'defer' to some late time actually changing their ways to pollute less directly - in effect it gives them a license to pollute to how many REC's they can purchase from the market. In effect they have no real 'incentive' to directly change...

News Update (27/10/09)

Apparently it has been reported in the main stream press (AFR) that the REC market is now flooded with cheap REC's ($50 per Mega Watt down to $30) due to the $1600 solar hot water subsidy causing a spike in demand. This has perturbed the market so much that large scale wind power projects are unable to compete in the energy market and are not being built. The end result is that the current energy producers have less 'green' competition to deal with; and this was not foreseen...

Solar panel installation considerations

How solar panels are configured to provide the most power output is quite important, you need to think about the following:

• Good visibility to the Sun. Having lots of trees and buildings in the way of your solar panel and the Sun as it tracks across the sky is not going to be good for producing reliable power you can do something with. Therefore check for good solar access, its critical. Must people mount their solar panels on their roof, but do ensure the roof surface runs 'true' East-West and not just magnetic East-West
• Ideal mounting angle. You want to have the solar panel as 'square on' to the Sun as possible. This is both the vertical and horizontal angle. The vertical angle slowly changes over the sessions as in Summer the Sun is higher in the sky than in Winter. The horizontal angle cycles from facing East to West every day as the Sun passes overhead (15 degress each hour)
• Maintenance access. You will need to make sure that the solar panels are cleaned about twice a year to remove dirt and bird droppings on the panels to ensure they operate at their best. Therefore either being able to get up to them directly, or at least remotely reach them with some spray or cleaner, needs to be taken into account.

As regards how the solar panels are mounted they usually come in three forms:

• Fixed mount - the vertical and horizontal angles are set to a sort of average over the year for picking up solar power. Not great but if you have a limited budget better than nothing. The panels need to be aligned to 'true' solar North (i.e. on a true East/West line) and not the magnetic North as this will skew your alignment out by around 11 degrees and reduce your power output. if the property they are being put on has been designed to benefit from Passive Solar the whole roof could well be in the correct alignment.
• Adjustable mount - with these the vertical angle can be easily adjusted by hand, so depending on the sessions you can change the tilt to improve the power collection. Again align to true solar North.
• Powered tracking mount - these mounts are essentially on a powered mechanical gimbal that tracks the sun across the sky. Maximizing the power harvested, but also requiring occasional maintenance as you now have moving parts.

One important consideration when mounting on a roof is to make sure that the back of panels have adequate clearance to cool - if the panel itself gets too hot it progressively losses efficiency. You will need a minimum of 100mm clearance behind the panels to ensure sufficient cooling. Also having this clearance is a good idea anyways, as it stops leaves and other 'junk' accumulating behind the panels and becoming a fire risk (bad news in Australia!).

NEW We have just put together an online solar calculator to help you work out the number of panels you will need.

NEW We have also just put together a cable gauge calculator to help working out the size of wiring required from your solar panels to either the battery or inverter.

NEW We also have a Financial Calaculator for working out the potential gain from a quote on the installation of a solar system.

Using an Installer - read the contract small print..

Something to be very careful with is that a lot of installers are saying their systems are 'guaranteed' for 25 or 30 years. Do please check the following:

• Exactly 'who' is the guarantee with when finally installed, i.e. what happens if the installer goes bust, does the guarantee fall back to the original manufacturer?
• Whats the guarantee on the other components in the solar system, in particular the inverter - these often have a working life of around 5 years tops and cost anywhere from $800 upwards to replace (i.e. 25/5 * 800 = $4000 to keep running over 25 years).
• Check on your house insurance to make sure 'acts of nature' do cover the solar panels.

Solar power energy consumption

One thing you will soon notice doing the maths on your power consumption is how much power does get consumed without you noticing! This comes from several sources:

• So called 'phantom power', basically all those consumer devices left on standby.
• Answering machines, wireless phones, chargers, etc
• Alarm systems, timer switches, irrigation controls, etc

We suggest you have a good look around your house and before making a decision on whether to go solar, see what you can just turn off and measure your power consumption then..

Other Solar options

You don't need to go the 'whole hog' to get benefit from solar power, especially when trying to use solar around the home. Consider these usage cases:

• Solar powered garden lights - these are ideal for running off solar either using standalone lights with built-in solar panels, or a common solar panel running a series of lights. Both systems require some form of battery storage to allow the lights to operate at night. The big plus with the standalone lights is that if you suffer a power cut you have easy access to lights you can bring in and use. Often use is made of LED lights to keep the power consumption down, you get slightly less light with these, but they last many times longer.
• Solar powered water features - there is a lot of pump technology designed to run off 12v supplies, so ideal to use for to power water features or just to pump water to a higher storage place in your garden, so you can do gravity fed watering.

Why go Solar?

Big question - it really comes down to two things:

• The value you place on the financial return, and,
• The value you place on the damage to the environment being caused.

Everybody is very focused at the moment on green house gas emissions but we think this is missing the point - there is a very large 'embedded cost' element in having services, like electricity, supplied to your house or business. This has a general environmental impact in consumption of materials. Therefore if one is able to operate 'without' the grid that cost does not get incurred, but if you already have the grid to your house, the cost has already been incurred, so going solar will not change that one bit.

Essentially the best way you can help the environment is to reduce your general energy consumption first, then look at using solar if you energy consumption pattern would benefit from it.

Note: Solar panels in of themselves should not be considered to increase the value of your property; given the rate of improvement in the underlying technology (and the reducing cost base) the current generation of solar panels are likely to be superseded by cheaper and more effective panels in the future. It is very likely the intrinsic value of the panels will decrease over time, you should factor this into your financial calculations.

Related Books

• Photovoltaics: Design and Installation Manual
  With this book a world-class solar energy training and education provider-Solar Energy International (SEI)-has made available the critical information to successfully design, install and maintain PV systems. The book contains an overview of photovoltaic electricity and a detailed description of PV system components, including PV modules, batteries, controllers and inverters. It also includes chapters on sizing photovoltaic systems, analyzing sites and installing PV systems, as well as detailed appendices on PV system maintenance, troubleshooting and solar insolation data for over 300 sites around the world. Used worldwide as the textbook in SEI's PV Design & Installation workshops.
• The Renewable Energy Handbook: A Guide to Rural Energy Independence, Off-Grid and Sustainable Living
  Author/engineer William H. Kemp, who is a leading expert in small- and mid-scale renewable energy technologies, designed and built his own off-grid home. The result is a house that has all the standard “middle-class” creature comforts while using less than five times the total fossil-fuel energy of the average North American house.
  The Renewable Energy Handbook focuses on the unique requirements of off-grid living and contains chapters on energy conservation; heating and cooling; backup power; domestic water heating; wireless communications; photovoltaic, wind, and microhydro energy generation; battery selection; and inverters.