It might seem strange but solar energy can be used for both heating and cooling down a building, provided the right technology is used.
Passive solar technology offers direct and indirect gain for heating spaces, water heating systems, use of thermal mass and also phase change materials which are able to control the temperature inside a building.
There is also equipment for solar cooking and something called the solar chimney which makes it possible to ventilate a building by using the principle that hot air rises.
Passive solar can also be found in such things as the solar furnace and the solar forge, even though they are a bit more complicated. Sun rooms are just one instance of using passive solar power as they let the sun enter the property and trap it, using materials that allow for this.
There are several ways that we can provide heating and cooling to our homes, businesses, buildings or other structures that need to be heated or cooled. Using free energy from the sun and passive solar technology can pay for itself instead of using artificial heating or cooling powered by non-renewable resources.
Passive solar technology turns sunlight into heat that can be used for several things, including ventilation and cooling. They depend on gravity fed and natural resources in order to make them work.
Adapting your home to use the sun as a supplementary heating source is not that hard to do. Although you can’t change the direction at which your home faces so as to get the benefit of the early sunlight, you can still collect much of the sunlight and reduce your dependance on other sources of heat.
Heating homes, schools or businesses with solar energy is not only easy but can be cost effective as well. There are several ways that we can capture the sun’s heat even during a cold winter as long as the sun is shining.
It is a well known fact that the sun is the strongest from the south. So, if you are building a home to utilize solar power more effectively, it is best for the windows to face south.
In order to capture the sun’s heat you need something that will receive the sun rays and trap the heat from it when it enters. A good example is a sun room or conservatory. These are attached to a home or a building and have a large area of glass panels to allow lots of sunlight in.
You may choose to add a sun room onto the side of the property which receives the morning sun allowing it to heat up naturally. With this in place you can then install ceiling fans that will circulate the warm air into other parts of the house.
When the sun shines into the room the glass allows the sun rays to heat the furniture and everything in the room. They are usually situated where they can take full advantage of the sun in order to get the full effect of the heat.
The objects and materials in the building will absorb and hold in the heat whilst the sun is shining and then disperse the heat when the sun goes down. The time lag property of thermal mass allows the use of fluctuating daytime solar energy as a more uniform night-time heat source. This way of trapping solar energy can be very efficient if it is constructed correctly, in fact it can sometimes be too efficient and shading may be required at times.
During the day this may well provide enough heat to maintain the warmth in your home. When modifying your home to make the most of solar power, it helps to install windows which are constructed from special materials which allow the heat from the sun to enter the house and prevent it from escaping.
A passive solar water system employs a solar collector that is joined into the home plumbing system. A solar collector can be a conventional water tank with a small number of modifications to attract more sunlight or it can be a flat plate collector that increases the efficiency in which heat can be transferred to water. A flat plate collector is basically a winding length of tube on a flat plate that is painted black. Water flows through the tube and the black-painted plate absorbs solar energy and transfers heats to the water as it passes through.
An example of capturing passive solar energy is the Trombe Wall. This is a natural solar heating and ventilation system that uses air channels to trap the heat between a glass object and a thermal mass that is facing the sun.
It is basically a massive wall separated from the outdoors by glazing and an air space, which absorbs solar energy and releases it selectively towards the interior at night. The sunlight gets trapped and stored inside this wall and is then circulated though vents and the top and the bottom of the wall.
Transpired air collectors are a low cost way to heat ambient air. They are generally wall mounted to capture the lower sun angles in the winter months, additional sun reflection off the snow and they also capture heat loss escaping from the building which is collected in the air cavity and drawn back into the ventilation system.
Solar Energy for Cooling
Solar energy can be used to reduce the temperature in a building and one way is with a solar chimney.
A Solar Chimney is a solar ventilation system made of a thermal mass that is hollow inside. Solar chimneys are painted black so that they absorb the sun’s heat more readily. When the air inside the chimney is heated by the sun, it causes the air inside the chimney to rise, creating an updraught which ventilates and cools the building.
A solar chimney may improve the natural ventilation and passive cooling of buildings on still hot days thus helping to reduce the use of air conditioning.
In cold weather we all need heat but to save money we also need to find out the best ways to save the heat from the day and use it to keep our house warm at night. As we have seen passive solar energy can be used not only for heating, but also for cooling and ventilation too.
Taking advantage of the sun’s energy to heat your home is a great way to save money on heating bills and also puts less strain on the environment. You can still have a backup heating source in case the amount of sun you get can’t heat your home sufficiently during the day. No matter what you do you will still reduce the amount of electric or gas you normally use, which can’t be a bad thing now, can it?
