PV Gap

Emma Said:

how can we have safe and sufficient energy for future development?

We Answered:

I am reminded of an Evaluation Dept study (under Planning Dept) done long ago in AP state, on the impact of a self reliant energy village project in a tribal (lambadi) village:

several depts of the state and centre, local industrial house, a NGO and the people united to generate self reliant energy for local needs - for cooking, street lighting, community TV etc

the local industry house provided a fenced land for growing fuel trees, a community TV room, a watch man and panel for tapping solar energy to run the TV..

the Rural Dept provided a community Bio gas plant for supply of gas for cooking to the houses. For getting the dung for gobar gas plant, the available milch cattle were not adequate and it was proposed to give loans for purchase of milch catle for more families to provide income as well as supply dung for the plant..

the cooperative dept proposed to give loans for the purchase of cattle by the willing locals..

the Alternate Energy dept gave free solar cookers to each family..

the NGo coordinated the work once the project was inaugurated with much fanfare by a central minister invited for the occassion by the state officials and wide publicity in media..

after a decade, the evaluation dept went for an assessment of the energy produced from the project for attaining self sufficiency...

it found that the solar cookers were not used by the tribals who were chapathi eaters (Wheat cake) which could not be cooked by it..

the fenced fuel farm was in spoils by tresspassers who cut the wood and no replanting done..

the watch man provided by the industry for initial watch was withdrawn and there was no protection to the farm..

the community bio gas plant was not functioning as there was no adequate supply of dung and the addl milch animals proposed were not provided on various grounds..

the community TV was however functioning as also some street lights using solar panels..

thus it turned out that a multi-lakh project started with much hope and preparation was in near total spoils..

the state of macro admin is no better.. the govts talked of alternate energy generation when the last fuel crisis struck by surprise.. but the moment the problem was resolved, all the plans for alt source of energy were given up..

now the projects of wild castor cultivation etc under wasteland dev scheme, for bio diesel production in various states are progressing sluggishly..

this is just to prove that the govts are not serious to solve any problem however serious and he public is also totally unconcerned with the impending crises like the energy and water scarcity...

unless public education is intensified and much pressure is mounted on the govt we can not expect any serious action from the govts

Marcia Said:

How many ways can a car generate its own electricity as it travels?

We Answered:

Solar power, wind power, and i'm no expert but just the wheels turning could generate power...right?

Robin Said:

A small island has to generate its own electricity from coal.?

We Answered:

A. If the question is a straight swap - get rid of the coal power station and build wind turbines and solar panels then no. What happens on a wind free evening in the middle of winter? Everyone wants to cook dinner, put the heating on and turn the lights on, perhaps with the TV as well - but no power can be generated. So no, I would not recommend that.

If the question is to build the things and keep the coal power station as a back up for the windless, cold nights then yes, consider building the renewable solutions. No calculations needed, just a bit of common sense.

Calculation time - Output from one wind turbine: 6 - is this just 6kw in which case you need 34,000 wind turbines running full power to replace the coal. Figure seems low. Perhaps 600kw and you need about 340 running ful time. That's a lot of windmills


B.
Cost is the big one - which will be cheapest in the next 5 years (people are short sighted)
Visual impact - draw what the scenery will look like
What heppens if they do nothing (apathy is thye norm)
Can they replace the coal with other fuel such as wood from managed woodlands

The manufacturers and met office can provide data for the units and average weather conditions for the island to do the sums

Debra Said:

Solar Energy converter?

We Answered:

Solar panels can produce electricity (just a wee bit albeit) even in very low light levels. In fact, I've heard of folks who have said they get a voltage reading across their solar electric panels on their home under bright moonlight. That said, the amount of power being generated at that low lux is of course low.

Solar panel manufacturers rate their modules assuming 1000 watts per square meter of sunlight. This amount is approximately the power sunshine produces on a clear day pointing directly at a solar panel. In terms of lux, this is just a simple conversion:

1 Lux is equal to 0.001496 watts/square meter

or

668,449 lux = 1000 watts/square meter

Solar panel technologies range from 8-17% efficiency. So that means that say a solar panel that is 15% efficient (in converting direct full sunlight to electricity) and let's say is 1 meter squared in size then it would produce 150 Watts (1000 Watts/square meter x 0.15 efficiency x 1 meter) or 100,267 lux.

Of course if the sun is not shining directly at the solar panel then it'll produce less power - with the extremes being at dusk and dawn usually. Solar panels can actually produce more power than what they are normally rated for in full direct sunlight. This effect can occur when there's reflection of sunlight from nearby water (e.g. a lake or a pond) or snow. The reason for this is of course that more light, more Lux is falling on the surface of the solar panel.