Renewables
In the scope of an energy saving project, the final goal of climate protection can be approached in two ways: by increasing energy
efficiency (proper use of power and heat, avoiding waste) and by climate-friendly energy production. The keywords here are: renewable energies from sun, wind, water and biomass.
This section provides information on how to use renewable sources of energy in school. The basic question is not whether you wish to build a solar system or wind-powered system. It is more important to decide whether the emphasis should be on a didactic presentation of the basics to reach as many pupils as possible or whether the most important goal is to build a system with the highest possible production (power or heat), or how to combine both goals.
Renewable energy sources share one significant feature: there is no additional fossil fuel energy source required to use them. The renewable energy sources supply the products necessary for the conversion into energy as fossil fuels do today. These products include solid, liquid, gas fuels, combustible fuels, electricity and heat. As highly technical equipment is required to transform the renewable energy sources into energy, the costs play a decisive role.
Didactic goals
You would mainly like to introduce the subject of renewables to your pupils. A functioning system on the roof of the school building is less important for you.
This premise is supported by the fact that there are many schools with a solar system – of which the teachers and pupils have no idea. It is normally not visible since access to the roof is usually restricted. However, since a school is a place of learning, emphasis should be placed on showing the pupils that environmental friendly energy supplies are possible in the scope of renewable sources of energy.
But be cautious: older schoolbooks, especially older editions of physics books, often handle renewable sources of energy in a derogatory manner. The data and facts are often out of date. For example, certain books still maintain that the production of a solar cell system consumes more energy than it produces in its lifetime. This is not true: A modern system produces at least four times more energy than it consumes. Cost structures have also changed in the past years. Certain solar-thermal systems have become economical and wind-powered systems have been producing economical power for a long time.
An alternative to the theoretical treatment of renewable energy sources is to build a model. The function of the system can be discovered while building it. One example is a model of a fully functioning solar-thermal system. This offers the advantages of comparably low costs and the fact that it can be built in the classroom and tested at the window.
An additional possibility, especially for higher-level classes, is to build solar models. The only basic equipment required for this are small solar cell modules and electric motors designed to work with them. Pupils have enough imagination to build modules that move with solar energy using various arts and crafts material available for them.
However, the wish to have an authentic solar power plant often arises within such projects. This could be even realized with pupils. There are do-it-yourself solar power plants which are cheaper than ready-made ones.
A real solar power plant
Many schools considering energy saving projects also want to generate energy seriously. Being a producer of power or heat is a great feeling. Furthermore, this also avoids climate-damaging carbon dioxide emissions as are produced in conventional energy generation.
The following PDF-files offer information on obtaining a photovoltaic, solar-thermal, or wind power system and summarize hints for their implementation:
photovoltaic system
solar thermal system
wind power generation
Remember that placing a system on the roof of the school will not ensure that all users of the school, especially pupils, will be interested in it. The power generated from an average solar cell system with a peak performance of about 1 to 5 kilowatts is only a fraction of the amount normally consumed at school (less than one percent). Therefore, you must always keep in mind that the use of renewable energy sources is mainly advantageous for pupils in their regular lessons.
Didactic goals and the real powerplant
At first glance, this may seem difficult: On one hand, the pupils should be experienced and understand the subject of renewable energy. On the other hand, a functioning solar or wind-powered system is to be set up to supply heat or power.
Both goals can be combined by simply building the system together with the pupils.
How can that work out? Don't you have to be a trained solar system installer to do this? That is true, but they do not have to do all the work alone. Specialists are necessary to install the electric or water lines. But there is a lot of work that can be done by teachers and pupils.
Several schools have gone ahead in this way, installing their own solar system and saving money at the same time.
Click here for information sheets on renewables.
