Technology Salon

Washington DC

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a discussion at the intersection of technology and development

Solar Power’s Twin Challenges of Sizing and Support

At the Technology Salon on Rural Power Solutions for the Developing World, Eric Youngren of Solar Nexus International started us off with the basics, and I learned about the difference between power and energy:

  • Power is the instantaneous creation and use of electricity – what is needed right now to power an electronic device, and is expressed in watts or kilowatts.
  • Energy is the storage of power for use over time, and is expressed in watt-hours or kilowatt hours.


We quickly moved from understanding a common lexicon to how electrical costs can add up quickly in the developing world.


Eric Youngren’s Solar Nexus

Sizing Solar Power Systems

With a real-world example from Ashoka’s e Health Point, Eric led us through a sizing exercise to understand what uses electricity and how much that usage costs – in power creation (solar panels), energy storage (batteries) and power consumption (electronic devices).

Now there is much math that is needed to size a solar panel array to meet energy storage and power consumption needs – everything from the efficiency of the solar panel to the site’s geographic location. You can get a sense of this by using Matt Berg’s Off-Grid Solar Calculator, though its best to have a trained professional do the sizing.

There are numerous efforts around making both the solar panel sizing and deployment easier – from companies building modular turnkey solutions to others devising pay-as-you go financing. Luis Antonio Vargas of World Vision International even talked of “smart grids”, where individual homeowners and businesses could feed into and take from a combined electrical system.

Capacity Building

But before we get to that, there is a great need for more solar power skills and knowledge at the local level in the developing world. Programs like Barefoot Solar Engineers are not enough to expand the use of renewable energy sources.

There is a need for both capacity building and standardization across the power marketplace, to truly make these systems sustainable. Or as one participant said, “Solar systems last 20 years – we need to plan in decades, not project cycles.”

I was honored that Eric referenced the Inveneo Certified ICT Partner program as a model for his efforts in building local solar power capacity – our mix of training, certification, and income opportunities for local technology partners. Yet, regardless of the model, the need is great, for electrical power and the skills to deploy it in the developing world.

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