Project data
Completed 2006
Cost USD 700
Instance of Shelter
Download Open Know How Manifest
Page data
Type Project
Keywords battery, efficiency, electricity, energy, hexayurt, household, load, module, Solar, renewable energy, solar panel, battery charger, power pillar
SDG Sustainable Development Goals SDG07 Affordable and clean energy
SDG09 Industry innovation and infrastructure
SDG15 Life on land
Authors Megan Moore
Published 2006
License CC-BY-SA-3.0
Affiliations Hexayurt project
Language English (en)
Impact Number of views to this page. Views by admins and bots are not counted. Multiple views during the same session are counted as one. 596
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Substitute for national grid or heavyweight solar with:

  • One 80 watt panel connected to a 15 minute AA battery charger (e.g. the new generation Rayovacs)

These items will be connected into a "power pillar" - a walk-up charging station where people come with their empty NIMH batteries, drop them into the charger, wait 15 minutes, then take them home. Assuming a 10 hour charging day, that services 40 sets of batteries.

Each AA NiMH battery has a capacity of approx 2000 mAh at 1.25V, equivalent to 2.5 VAh. If charger efficiencies are 25% (my guess) then we need about 10 Wh to charge each battery.

80 W for 10 hours is 800 Wh per day or enough to charge 80 batteries a day.

Applications for this system include:

What won't work:

  • Heavy-draw mains appliances (toasters, video projectors)

Financial model:

  • $400 for the panel, $100 for the charger and pillar. ($12.50 per household)
  • $200 for 80 fast charge AA batteries say 4 each for 20 households.
  • $100 or 20 lighting units.
  • $700 total or $35 each for 20 households.

$50 per household should comfortably buy everything required for basic electrical services. A bare bones system (lighting and stoves only) would be about $12.50 per household because the cost of the panel, charger and pillar could be split between 80 households.