Solar energy has a simple but annoying weakness. It disappears when the sun does. Even the most efficient systems struggle with this basic reality—no sunlight means no power. Scientists have long tried to fix this by storing solar energy as heat, but doing it efficiently has proven tricky.
Most designs rely on stacking different materials together—one to absorb sunlight, another to store heat, and then another to protect the system. These layers don’t work seamlessly, wasting energy at every boundary.
Now, researchers have taken a very different approach to overcome this problem. Instead of assembling multiple parts, they’ve turned wood into an all-in-one solar energy system.
By redesigning its internal structure at the nanoscale, they’ve created a material that can absorb sunlight, store it as heat, and keep generating electricity even after the light is gone.
frustrating finding out if this is useful or not. 179kj/kg is about 50wh, bad. Thermoelectric being at 8% tops efficiency also means you get out about 4wh per kg, and so terrible storage.
0.65v guessing from other thermoelectric data sheets would be 0.65w/sq.inch, but that is close to 1100w/sq. meter. At about 30C hot-cold difference. But it will take a long time to heat up if it takes a long time to cool. Still that seems good power per area. 1000w/sq.meter is solar input, so that peak power would be after a good 8 hours of sun input
To be useful they need to make specific claims about power/sq.meter, and power per full day. I’m just guessing from above, but this could be about 1kg per sq.inch, and 1.6tons per square meter.
The same power/day could be generated from a sheet of black metal, which would be much cheaper. A dark metal tank of water would serve the same battery feature, or parabolic mirror onto a water pipe, feeding into a water tank.
thermoelectric devices per square meter are much more expensive than PV solar