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Real Solar Power Self Efficiency Solar Energy - Real Power hen you hear of remote area power systems in the media or in government brochures, solar electric power is por-]} New Light Technology trayed as a less attractive option despite many recent advances, 1 A t . : p ights on the other hand present a This recommendation against solar electric power is based on an} puch brighter picture. Quartz-Halo- extravagant and wasteful lifestyle. gen Bulbs are now designed to operate ona low voltage system more We often take for granted that the | plied with an appropriate low volt- | efficiently thanona high voltage one. whole house ought to be lit by stan- | age DC motor. Spending a little extra on more effi- dard 240 volt lights with power- Ina car everything from cranking | cientlighting can help you savein the points throughout. This dictates a | the engine to running the air-condi- | overall size of the solar array, You substantial battery bank poweringan | tioning unit is done quite adequately | gain the extra benefit of having a appropriately sized inverter (pro- | with low voltage DC. In fact it is | superior quality of light (a spectrum ducing high voltage AC from low | generally recognised that low volt- | similar to daylight). voltage DC) to cope with constant | age DC motors have more torque In the average 240 volt household demand. than a 240 volt motor of the same | there is no attention paid to how wattage rating. Why then are 12 volt | much power an appliance uses. With Transformers Unnecessary | vacuum cleaners so weak and gut- | refrigerators, for example, the em- Many electronic gadgets in your | less? Because they have been de- | phasis seems to be on space saving home depend on getting their power | signed to be cheap and not to use too | rather than efficiency, hence they through a transformer which steps | much power in order to make the | have thinner walls but need more down high voltage AC toa low volt- | battery last longer. The same job | power to stay cool. Ideally, the refrig- age AC. In most cases the power | could have been done in minutes | erator should be of the low voltage would be as well supplied by a low | using more power but overa shorter | compressor motor type and prefera- voltage DC power supply (without | time. bly top opening. needing the transformer) and could Another argument in favour of easily be supplied by a battery bank. low voltage is the safety aspect. DC is Both the inverter and the trans- safer than AC. Anything less than 120 former are considerably less than volts DC is not considered lethal, 100% efficient, and powering one whereas with AC you need to come with the other just compounds the as low as 32 volts! There is still a fire inefficiency. You can run many low hazard, however with low voltage voltage gadgets direct from a battery DC so you must protect the system bank. Where you do need higher with the appropriate fuses and/or voltage, such as is required by a TV circuit breakers. tube or electric fence, you need a specialized inverter to supply that Tuntable Turntable The Rainbow Power Company of voltage. Australia still has vast areas that Nimbin, incorporated as a company are remote from any power grid. Itis in July 1987, has developed several unfortunate that the government has low voltage DC kitchen appliances recently put the 12 volt TV into a and specialises in high efficiency low higher taxation bracket, because it is voltage lighting. It will soon be mar- regarded as more of a luxury item 7 p=* keting a modular hi-fi system (in- than its 240 volt counterpart - but the cluding turntable) and is developing recent RAPAS grants [see last issue] With appliances thatare designed | a low voltage washing machine. If are a promising step.. to generate heat, such as stoves and | you want some advice on a more What about such labour saving | hol water systems, one could look at | sustainable alternative and comfort- appliances as: food mixers and proc- | alternative ways of generating that | able lifestyle, come and ask them essors; laundry machines; workshop | heat:bottled gas, firewood, sunshine, | about it (or write). They’re not just tools; sewing machines and vacuum | biogas-or producing the heat electri- | selling it, they’re living it = cleaners? These could be run just as | cally if the electricity can be gener- - Peter Pedals well, if not better, if they were sup- | ated cheaply enough. NEXUS New Times Four - Autumn 1988 Self Efficiency New Light Technology Tuntable Turntable