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Granny Converts Old Honda into Electric Car Herself

A New Zealand grandma has found a way to be the change she wants to see in the world.

Rosemary Penwarden standing beside the electric car she converted herself
Credit: Rosemary Penwarden

Sixty-three year old Rosemary Penwarden converted an old Honda into an electric vehicle that she charges with home solar panels.

Penwarden purchased the 1993 car from a wrecker’s inventory, removed the combustion engine and installed a new gearbox and electric engine in its place. She also added 24 batteries to the front of the car and 56 to the trunk. The car can travel 120 km (approx 75 miles) before it has to be charged. While Penwarden did the work herself, she also had help from other members of the Valley Workshop cooperative that she helped found.

“It took probably 8 to 10 months of pretty solid work,” she told

The entire project cost her $24,000. For comparison, the average price for a new electric vehicle is around $65,000. However, this intrepid grandmother and her colleagues didn't charge for the hours they put in.

Penwarden said she expected her self-made car to pay for itself eventually, since she used to spend as much as $100 a week on gas. However, she said that she did not convert the car in order to save money and understood that not everyone has the funds and time to follow her example.

“Just to be able to show that it can be done is a priceless thing,” she said, as The Guardian reported. “The biggest thing is to help stop the biggest polluters as soon as possible – and nothing that we can do as individuals I think matters quite as much as that.”

Penwarden isn’t the only one in her community converting conventional cars into electric vehicles. Fellow Valley Workshop member James Hardisty owns a car conversion business called EV-lution, according to He said that he had converted around 15 cars, and the Toyota RAV4 he turned into an electric vehicle around 2010 still drives on the same battery.

“It’s great for the environment… you don’t have to worry about what’s happening in the world, if there is a war… if all the oil was to dry up tomorrow, we’d keep going,” he said.

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