A nuclear fusion reactor in China, dubbed the "artificial sun," has broken its own record to bring humanity one step closer to near-limitless clean energy.
Yes, of course, there is financing and everything else. I was getting a bit deeper:
If you have to spend 100 joules building a power plant, it better give back more than 100 joules during its lifetime - otherwise it was never worth it to build. That isn’t strictly true, there are special purposes, but certainly as a grid-scale energy deployment you would need - at a bare minimum - for each plant to pay for itself in terms of energy investment.
The dollars follow from that physical reality.
The first hurdle for fusion to clear is that the reaction outputs more energy than it needs to sustained. This would be a great academic success, and not much more.
The second hurdle is that it outputs enough energy such that it exceeds the sustainment energy even after accounting for capture losses (e.g. from neutrons, turbine efficiency, etc.) and production efficiencies (lasers need more energy input than they impart to the reaction chamber, magnets need cooling, etc.).
The third hurdle is that over the lifetime of a plant, it produces enough excess energy to build itself and pay the embodied costs of all maintenance and operations work. If the reaction is technically energy positive, but you need to replace the containment vessel every 48 hours due to neutron embrittlement, then the plant better be productive enough to pay for refining all that extra steel.
The fourth hurdle is then that it produces more excess energy per unit of invested energy than any other form of power generation - at which point we’d never build solar panels again.
These final hurdles are in no way guaranteed to be cleared. Artificial fusion needs to be orders of magnitude denser than natural fusion (Stars) to make any sense… a fusion power plant the size of Earth’s moon, with the same power density as the Sun, could only power around 1 million US homes.
a fusion power plant the size of Earth’s moon, with the same power density as the Sun, could only power around 1 million US homes.
Capital costs alone are prohibitive.
TIL/google ai:
The power density of the sun at its core is about 276.5 watts per cubic meter ((W/m^{3})). This is similar to the power density of a compost pile, but lower than the power density of an adult human’s metabolism.
ok. wow. But solar energy reaching earth can be converted to electricity by commercial PV at 250w/m^2. Even in US installed at under $1/watt with 50 years of useful output, and under 2c/kwh unamortized energy costs. That seems like the actual bar to pass, which is impossible for fusion or fission.
Yes, of course, there is financing and everything else. I was getting a bit deeper:
If you have to spend 100 joules building a power plant, it better give back more than 100 joules during its lifetime - otherwise it was never worth it to build. That isn’t strictly true, there are special purposes, but certainly as a grid-scale energy deployment you would need - at a bare minimum - for each plant to pay for itself in terms of energy investment.
The dollars follow from that physical reality.
The first hurdle for fusion to clear is that the reaction outputs more energy than it needs to sustained. This would be a great academic success, and not much more.
The second hurdle is that it outputs enough energy such that it exceeds the sustainment energy even after accounting for capture losses (e.g. from neutrons, turbine efficiency, etc.) and production efficiencies (lasers need more energy input than they impart to the reaction chamber, magnets need cooling, etc.).
The third hurdle is that over the lifetime of a plant, it produces enough excess energy to build itself and pay the embodied costs of all maintenance and operations work. If the reaction is technically energy positive, but you need to replace the containment vessel every 48 hours due to neutron embrittlement, then the plant better be productive enough to pay for refining all that extra steel.
The fourth hurdle is then that it produces more excess energy per unit of invested energy than any other form of power generation - at which point we’d never build solar panels again.
These final hurdles are in no way guaranteed to be cleared. Artificial fusion needs to be orders of magnitude denser than natural fusion (Stars) to make any sense… a fusion power plant the size of Earth’s moon, with the same power density as the Sun, could only power around 1 million US homes.
Capital costs alone are prohibitive.
TIL/google ai:
ok. wow. But solar energy reaching earth can be converted to electricity by commercial PV at 250w/m^2. Even in US installed at under $1/watt with 50 years of useful output, and under 2c/kwh unamortized energy costs. That seems like the actual bar to pass, which is impossible for fusion or fission.