INDEX - ENERGYwww.islandbreath.org ID# 0614-15
SUBJECT: UNINTERUPTED POWER SUPPLY
SOURCE: JUAN WILSON firstname.lastname@example.org
POSTED: 18 December 2006 - 8:30pm HST
The Hawaiian Energy Appliance
image above: Electrical device to supply reliable power. Click for PDF spec sheet with cross-section
by Juan Wilson on 18 December 2006
I would love to be completely off the power grid with a large photovoltaic solar array and a silent wind turbine on my roof. These units could provide all the power that I would need. For insurance, I could have an array of reliable batteries to store energy when the trades are not blowing on a cloudy day.
The problem is that I cannot afford such a system. It would cost more than a luxury car. These kinds of systems are custom designed and installed. Way too much money for me. So my idea was to determine the "critical mission" I need power for and find a way to provide that energy off the grid.
I soon realized that the critical mission for me is running my home office day in and day out. My work is intricately locked into the internet and the computer. If the grid goes down I cannot get much work done. The tools related to my work provide me with much of my leisure entertainment, too.
For other people the critical mission might be lights for reading at night or power for their entertainment equipment. Other people might choose running a craft shop. Different critical missions for different people. The point is, we will probably have to adjust to using less power soon. Getting down to what is affordable and important is something we need to pay attention to.
I found a provider (APC www.apc.com) of Uninterrupted Power Supplies (UPS) storage units that you plug your critical equipment into. When the power goes out the unit batteries kick in and without a blip on your computer screen, you just keep working. These UPS runs on 110 volt AC and use lots of batteries. I sized a model that would run my office for eight hours even if the grid was shutdown.
It was beautiful. A single appliance that did it all: gathered, converted, stored and switched to an alternate source of power. I could get that unit for under $2,000 but there was one little glitch.
I wanted to use a single solar panel or small windmill to trickle charge the batteries while the sun was shining or wind was blowing. It would be a lot cheaper than building a whole custom roof array to supply all my power needs.
These UPS units used the grid's 100VAC but would not accept a direct current low voltage source of energy to charge from, even though the batteries stored the power in low voltage DC batteries.
My frustration was great enough that I bugged the APC company until they connected me with an engineer who was surprised anyone would want to hook a DC power generator up to one of his appliances. He thought it was a good idea and said he would tell his boss about it. That was about a year ago.
Well, in the meantime I have begun designing a prototype with the working name "Makini Uwila" - Hawaiian for "Electric Machine". I also tried "Puhu Ikehu" which translates as "Energy Box". Anyway, the idea to to make an appliance about the size of a washing machine that could fit under a kitchen counter, or be a side table in an office, or be the unit you put your home entertainment system on.
It would plug into a wall outlet and store about eight hours a day of power to run a "critical mission" it could be easily hooked up to a small quiet residential wind turbine (like the one by AeroVirenment) or a solar voltaic panel (like the 90watt one from BP).
With this simple appliance, KIUC could be down or even out of business, but you wouldn't be. Maybe some military contractor like Bendix or Raytheon could get off their ass and do something useful about this.For more about the Makini Uwila prototype check out this 500K PDF file.