Popular Mechanics (South Africa)
OFF GRID INNOVATIONS AND THEIR I HARVEY ARE THE WINNERS OF THE POPULAR MECHANICS READERS’ INVENTOR OF THE YEAR AWARD AT THE SA INNOVATION SUMMIT INVENTOR’S GARAGE.
The idea started in 2011, when the tablets-as-textbooks-replacement cart was placed before the underpriviledged- children-don’t- even-have- electricity horse. Luckily, the founders quickly changed strategy to better serve the needs of the communities they first identified.
‘According to Statistics South Africa, 49 of South Africa’s 213 local and metropolitan municipalities maintain they are “servicing indigent households with at least one form of off- grid energy”,’ says Allan Goldberg, MD of Off Grid Innovations. ‘ We decided to investigate the possibility of using photovoltaics (solar), but soon realised we would have to rethink our idea because of the required size of the panel needed in order to provide reliable functionality in all weather conditions.’
That, combined with the setup and maintenance costs, as well as not being completely user-friendly, meant that the company had to look at other alternatives. During this time, Goldberg, an electrical engineer by trade, was experimenting with thermoelectric power- generating modules that harvest energy using the Seebeck Effect: when a difference in temperature between two different electrical conductors produces a voltage difference between the two. ‘ This made us wonder whether we could we produce enough usable electricity using heat sources most off-grid households use without having to modify them.’
At this stage, Goldberg approached mechanical engineer Paul van Lingen with his idea, who suggested a paraffin lamp be used as the heat source. Some 18 prototypes and multiple variations later, the pair realised that standard wicker holders and chimneys caused too much heat loss to allow the system to produce usable electricity and that led to the design of the wick-based burner.
Thanks to his experience in combustion control, Van Lingen was able to produce a burner which reduced emissions by 83 per cent and reduced emissions from 40 mg/m3 down to 0,01 mg/m3.
The new burner provided enough heat thanks to a design that optimised heat rather than light as the primary function – which is how standard paraffin lanterns operate.
‘ The TEG structure and electronics were optimised to give us what we have today, which is probably one of the most fuelefficient power generators on the market,’ explains Goldberg. ‘In December 2012, we made prototypes in order to test our design and show off the functional product to investors.’ The design was well received, and the unit is now almost exactly the same as the successful prototype, with a few minor aesthetic changes. Ferrotec joined as partners shortly after, and iharvey was born.
You can buy an iharvey for R1 500 at sustainable.co.za
́ iharvey is just the beginning, and our promise to you is to never stop exploring and developing innovative and affordable ways to bring basic electricity and modern accessories to those who need it ́