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Dim thinking behind the new lightbulb laws

This is excerpted from an interesting blog - and I sort of agree with what the author says The hoarders were out last week. We learnt that the Germans have been stockpiling old-fashioned lightbulbs to beat this week’s European Union ban on making and importing pearl and frosted traditional bulbs, yet you might have expected this ever-so-green, tree-loving nation to be marching out to buy the energy-saving ones. I talked about it to James Shortridge, who runs the Ryness chain of lighting stores. Apparently we Brits aren’t so different ..... ...... You can read more at the original source - click on the title or anywhere on the text.
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Hydroelectric for Goa

Its been raining continuously for the past 2 days here in Goa. And just a while ago while I was reading about small hydroelectric systems in Home Power I thought yeah we can implement this to complement solar PV. At this time of the year we have little sunlight... it gets overcast and it rains for a couple of days (at the minimum) on end. There is water gushing from the drain, from the roof and from freshly formed streams. Small Hydro can make up for the loss of sunlight. How about placing tiny systems at downspouts and fast flowing storm water drains. Just a thought... have to work on this Anyone reading can contribute your thoughts.
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What NOT TO design

This is an excerpt from TOI of 10-June. "Back in 1960's, American space agency NASA was faced with a major dilemma. Astronauts needed a pen that would write in the vacuum of space. NASA got cracking into developing the $1.5 million gravity immune 'astronaut pen'. At the same time, the Russians too were faced with the same dilemma. However, they used a pencil instead!" How very relevant. It is important that we designers do not lose track of the solution and go only after technology for technology's sake. We should use technology for Solution's sake.
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5mm LEDs and a real good light?

I recently came across an article which mentioned that 5mm LEDs are not suitable for general lighting. I do not agree with this view. A 5mm LED will produce much less heat and hence the heat can be managed with a proper PCB design and without using any heatsink. A correctly driven 5mm White LED will live its rated life, which in case of a good manufacturer is easily in the 30,000 to 50,000 bracket. The ageing of phosphor and gradual change in colour spectrum is an issue faced by all white LEDs and not only 5mm LEDs. For a neutral assessment check this US Government website: http://light.lbl.gov/technology-assessment.html I have designed and made a board with 18 numbers of 5mm (hat shaped for larger angle) white LEDs. This board is ideally suited for low light applications like stairways, corridors, and in some rural lighting applications. With LEDs from Yetda I have got very consistent light and colour. In my test I could get 47 Lux at 1 metre from the PCB. and about 170 Lux at 0.5...
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