Nuclear Fusion Still Requires 100X More Energy Than it Produces. Here’s Why.

Since Tuesday, the media has been excited about Nuclear Fusion.

That’s because a recent breakthrough experiment produced 3.15 megajoules of fusion energy compared with 2.05 megajoules of energy used to trigger the reaction, resulting in a “net energy gain.”

So why will it take decades to commercialize this? Are we missing something?

As it turns out, the 3.15MJ from 2.05MJ story is misleading, as the facility used 100s of megajoules of electricity to produce the laser light needed to produce 3.15MJ of fusion energy.

Real net energy gain requires a comprehensive measurement.

Input VS Output

What we’re really after is more fusion-based electricity than input electricity. If that ratio ever becomes positive, we have the seeds of a viable commercial product. If the ratio tops 15:1, that’s on the way to beating natural gas as a baseload energy source. If the ratio surpasses 25:1, it’ll beat coal. 20:1 beats solar, 35:1 beats wind, and 60:1 beats most hydro sources.