Germany just took fusion power one big, important step forward. The country's Max Planck Institute for Plasma Physics has just switched on Wendelstein 7-X, the first large fusion reactor based on a twisty stellarator design. It's only producing hydrogen plasma at the moment and won't actually generate energy, but power isn't really the point. Instead, it'll serve as proof that stellarators could provide energy while operating continuously, unlike current (tokamak-based) fusion reactors that operate in short pulses. They should be safer, too.
The inaugural test phase will run through mid-March, after which point it'll get an upgrade to let it run hotter and longer. Eventually, it should discharge for up to 30 minutes at a time, and muster a heating power of 20 megawatts.
The machine comes at a high price in more ways than one. It took roughly 19 years to design and build Wendelstein 7-X at a staggering cost of €1.2 billion, or about $1.3 billion. That's a lot of effort for a testbed device. However, it could pay off if it leads to a much more powerful (not to mention less dangerous) alternative to nuclear fission energy.