A "mechanical" nuclear fusion reactor, algae that is genetically modified to make ethanol and an electrical storage device that promises to power an electric car 800 kilometres on a 30-second charge. These are some of the clean energy technologies explored by journalist Tyler Hamilton in his new book, Mad Like Tesla: Underdog Inventors and their Relentless Pursuit of Clean Energy.

The Tesla in the title refers to Nikola Tesla, a Serbian-born American inventor who basically dreamed up the modern electrical system and pioneered radio and electromagnetism in the late 19th century.

However, Tesla had a reputation for having ideas so far ahead of his time that it was impossible for his peers to tell if they were visionary ideas or delusional fantasies. "And I thought to myself, 'Wouldn't it be nice if we had some Teslas in the modern day?'" said Hamilton, in an interview on Quirks & Quarks Saturday.

He decided to look behind the news stories about developing clean energy technologies, and try to find out how they were coming along and what struggles and barriers their inventors were facing.

What he wanted to do, he said, was "look at whether or not their idea actually is crazy or whether there's some potential for it to reach commercialization."

One of the companies Hamilton highlighted was General Fusion, which has built a prototype of a nuclear fusion reactor in a garage in Burnaby, B.C.

While other groups are spending billions, trying to figure out how to use expensive lasers or magnets to set off the reaction, General Fusion is relying on pneumatic rams that compress plasma by hitting the outside of a metal sphere, sending shockwaves through the liquid inside — a much cheaper method.

"A thermonuclear diesel engine is basically what it is," Hamilton said.

Company founder and president Michel Laberge estimates he will be able to produce a 200 megawatt commercial version of the reactor by 2020 and a demonstration prototype before then. He is seeking a $50 million investment and Hamilton said the company has started to attract serious investors, including Amazon founder Jeff Bezos.