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GCSE Bitesize was launched in January 1998, covering seven subjects. For each subject, a one- or two-hour long TV programme would be broadcast overnight in the BBC Learning Zone block, and supporting material was available in books and on the BBC website. At the time, only around 9% of UK households had access to the internet at home. [3]
The energy content in the global production of bioethanol and biodiesel is 2.2 and 1.8 EJ per year, respectively. [ 16 ] Bioethanol is an alcohol made by fermentation , mostly from carbohydrates produced in sugar or starch crops such as maize , sugarcane , or sweet sorghum .
Bioenergy feedstocks typically require significant amounts of energy to harvest, dry, and transport; the energy usage for these processes may emit greenhouse gases. In some cases, the impacts of land-use change , cultivation, and processing can result in higher overall carbon emissions for bioenergy compared to using fossil fuels.
As compensation, the BBC launched a section called Learning Zone Broadband, or more simply Class Clips which includes segments from Learning Zone as well as clips taken from other relevant BBC programmes. These clips were available to watch on demand over the internet for free.
Forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, the internal energy contained within a ...
An energy transition is a broad shift in technologies and behaviours that are needed to replace one source of energy with another. [14]: 202–203 A prime example is the change from a pre-industrial system relying on traditional biomass, wind, water and muscle power to an industrial system characterized by pervasive mechanization, steam power and the use of coal.
Microgeneration technologies include small-scale wind turbines, micro hydro, solar PV systems, microbial fuel cells, ground source heat pumps, and micro combined heat and power installations. [1] These technologies are often combined to form a hybrid power solution that can offer superior performance and lower cost than a system based on one ...
Renewable energy in developing countries is an increasingly used alternative to fossil fuel energy, as these countries scale up their energy supplies and address energy poverty. Renewable energy technology was once seen as unaffordable for developing countries. [ 200 ]