Steven Henderson of Britain has successfully built a large biodiesel processing system in his family’s barn. How? Using about £10,000 ($20,000 USD) worth of equipment - six huge tanks, pumps, etc. And… using 1,000 liters a day out of waste oil from local restaurant kitchens.

But why? The 15-year-old Henderson says, “I was worried about global warming and climate change,” he said. “And it saves quite a bit of money.” Fair enough. His family saves between £300-400 ($585-780 USD) a week compared to buying diesel. Steven also pumps hot water from the barn processing facility into the house; now the family’s hot water bills have dropped to nothing.