![A photo of an engineer working in the target chamber of the National Ignition Facility](https://cdn.mos.cms.futurecdn.net/FB4A8oUUeZk7vnQeXkX7DU-320-80.jpg)
Nuclear fusion could be the clean energy of the future — but these 'tough' challenges stand in the way
Even once researchers can reliably get more power out of a fusion reaction than they put in, they'll still need to overcome engineering challenges to scale up fusion energy.