Category Archives for "How It Works"

Solar Power System Design

Solar Power System Design For The Home.

The general layout of a residential solar power system design is shown in the image below (thanks to the Dept. of Energy). This article discusses the different components of designing a Solar Panel system for a home.

Passive Solar Energy

Passive solar energy is the use of solar power without any active mechanical devices to convert or act on the energy. This is opposed to the idea of active solar power systems which use solar panels to collect the sunlight and convert it into electricity. Generally passive solar designs do not require any conventionally generated or supplied power to run, however there are exceptions to this rule, where a small amount of power supplied by “normal” or conventional means is used to control aspects of the passive solar designed system. Passive solar power systems can be used to heat your home, heat your swimming pool, provide hot water for household use, and can even be used to ensure your home has good ventilation and air circulation.

There are also examples of bad passive solar design, in which rooms within a dwelling become very difficult to cool in summer and this can lead to inefficient use of power hungry air conditioner systems. Quite often, installing external shading or louvers can significantly improve the unwanted heating of a room by solar energy.

Adding thermal mass is often used to smooth out the highs and lows of temperature variation, so that a building can be cooler through the day and warmer at night. Practically this can be achieved in building design using some more traditional building materials such as stone or by adding thermal mass to the walls and/or flooring slab or support.

Solar chimneys can use convention to naturally move air by means of heating the air in an exposed chimney, which rises and in turn draws stale air up from a building below, and this technique can be very effective in ensuring air circulation without requiring electrically driven fans or other equipment.

Other uses of passive solar technology include solar cookers, which have solar reflective arrays or mirror systems to concentrate the sun's rays into a central area containing a cooking vessel. These have particular interest in remote or developing areas, where conventional electricity or gas or even wood supply for burning are just simply not available. More specialized uses of passive solar technology can include solar forges and concentrators for extreme heating of a small area. These require very careful alignment to achieve the necessary concentration of energy into a small central area.

In a truly modern energy efficient, green environmentally conscious building, there is a role for both passive and active solar energy systems. Good insulation, good building design principles and clever use of solar power panels and electricity generation schemes can all have a part to play in ensuring we reduce the reliance on conventionally generated power in our society.

Solar Energy – DC vs AC

DC and AC in Solar Panel Systems

DC Current

Photovoltaic solar electric panels, or PV modules, generate electricity by converting sunlight directly into power. The PV modules generate direct current, or DC electricity. DC electricity is what you’ll typically find in batteries. Direct current flows in one direction (more about this vs. AC below). DC is typically hard to transmit over long distances because the voltage can’t be easily increased. The source generation needs to be matched to the load and the distance from the load. In a long transmission line, the voltage drop is current * resistance or (I *R). Wire has a fixed resistance so you need a high starting voltage to overcome the voltage drop. Continue reading

Installation Steps for a Solar Power System

With electric rates on the rise again (another rise occurred for the new financial year), and yet more hikes predicted as government policy changes, homeowners everywhere are warming to the idea of installing solar panels on their rooftops and taking back some control of the household energy. This article will walk you through the steps to installing a full commercial system, such as those available from BP Solar, in your home. Continue reading

4 Benefits of Solar Panels

What are the benefits of solar panels on your home?

Installing solar panels on the roof of your home can be a great investment that saves you considerable money, helps the environment and also increases the value of your home. Over the last few years the use of solar panels within residential and farming housing has grown enormously, and with good reason. Not only do you immediately save on your utilities bill, also in a lot of areas there are fantastic government rebates and incentives.

Benefit #1 of Solar Panels for Your Home - Tax Incentives

This is one of the best times to build a solar power installation in the United States. The 2008 Recovery Act has some fantastic tax incentives for solar and wind power. These incentives are in the form of a tax credit which is even better than a tax deduction. Read more about the Tax Credits here.

Benefit #2 of Solar Panels - Costs are dropping

Costs of the panels have dropped over the last few years, and for those willing to put in a bit of “do it yourself” effort, armed with the right know-how the costs are even lower, and the step to free energy from the sun has never been easier. It is now possible to build solar panel or panels and assemble your own array to make the entry cost very low. See our build-it-yourself series of articles here.

Benefit #3 of Solar Panels - Becoming Self Sufficient

If you have suffered through a rolling blackout in Texas or California, you know what it feels like to feel helpless. The nation's electricity grid is sometimes over-whelmed and therefore not everyone can be provided electricity. The power companies will shut down different sectors for 1-2 hours at a time. If you are producing electricity locally with solar, you can still power some of your more important applicances such as refrigerators, etc.

Benefit #4 of Solar Panels - Selling excess electricity

Not only can the energy you collect from the sun using your own solar panel array compete with the conventional grid utility power supply in terms of cost, in some cases you can even sell your excess generated solar electricity back to the grid – how is that for reversing the utility bill situation!

How Hard Is It To Get These Benefits?

If your home is located in the northern hemisphere, and you have a good south facing roof area that is not too overshadowed and gets reasonable sunlight through the day, you have a ready made spot to put your solar panel array. If you are in the southern hemisphere, take a look at your north facing roof area as a good location for the panels.

These days solar panels make a convincing argument to switch from coal burning conventional “unclean” energy sources to clean, abundant, cheap power right where it is needed – in the home. The benefits of solar panels for your home are numerous and we'll start to see more adoption of solar panels as time goes on.

Sign up here for the Solar Power Newsletter to learn more about Solar Energy.