New trends in physics teaching, v.4; The ... - unesdoc - Unesco

Teacher education: solar energy
need to be curtailed. Experienced teachers working with whole classes were needed to look
into this.
EXTENSION TO IN-SERVICE EDUCATION
The experiment with student teachers demonstrated that a study of solar energy in school is
worthwhile, but that practical problems remained. Prototype apparatus had been built which
needed refinement and production in larger quantities. Laboratory suppliers are now supplying
some solar apparatus, but it is much cheaper to build it oneself and a teacher’s own preferences
can be incorporated into home-made apparatus. Three different needs of experienced teachers
were recognized. They need to know more about the whole energy supply question and the
economic and technical issues behind it. They need apparatus with which to work and they need
help in organizing lessons outdoors. Two evening courses were arranged for teachers each lasting
ten weeks. The first was a series of lecture-demonstrations covering not only the theory and
practice of small-scale energy provision, mainly solar and wind, but also discussion of the ways
in which the study of energy in school can be incorporated into and extended from existing work.
The second course was entitled ‘Build Your Own Solar Collector’ and a group of teachers
attended a purely practical course in which materials and tools were provided so that teachers
could take collectors back to their schools. At the same time, they were introduced to other solar
devices.
The original work had shown that more quantitative investigations could be carried out if there
were an instrument which could measure solar radiation density. A commercial solar pyranometer
was purchased as a standard and a much cheaper version was designed and built. The ability to
measure incident radiation in watts per square metre made a whole range of new calculations
possible. The calculation of efficiencies was now easy. We also needed a cheap, robust thermometer.
Mercury in glass thermometers are becoming too expensive for schools to provide and
they proved too fragile for the outdoor environment. As their price falls so electronic thermometers
are becoming a better buy for class use. To keep costs down, we have designed and built
our own electronic thermometer for use outdoors. We also realized that if children were to make
the most of their energy studies, they needed more data. A collection of data sheets was therefore
prepared [4]. The facts, figures and graphs contained therein were sufficient to permit
advanced study and calculations to be performed and enough information was given to help in
the design and construction of working installations. There is still much to be done and we have
only started on a widespread dissemination of our ideas. At the time of writing, six sets of solar
apparatus are in schools for evaluation by teachers, occasional meetings of teachers are being
arranged and visits are being made to schools. The apparatus and teaching materials are likely to
be adapted and developed continuously and we are confident that the interaction of university
staff, experienced teachers and students-in-training wil continue ‘into the foreseeable future and
that a study of energy covering far more than the physics of the 16th to 19th centuries wil
slowly come to be looked upon as an essential component of science courses.
REFERENCES
1.
2.
ION, D.C. Availability of World Energy Resources. London, Graham & Trotman, 1980.
SINGER, S. Fred (Introd. by). Energy: Readings from Scientific American. San Francisco, Calif., W.H.
Freeman, 1979.
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