Globally we produce A LOT of #energy, but did you know the majority of fossil energy gets wasted? In the US alone, two-thirds of that energy is *wasted* as heat.
As Hannah Ritchie has pointed out, we don’t actually need to produce a low carbon equivalent of all of the coal, oil & gas we currently use.
That means we can decarbonize quickly by being less wasteful & more efficient. #ClimateChange #science
@Sheril Yes, ~60-70%-ish losses are normal in thermal generation processes due to the limits of the Carnot cycle. In cars (small machines, most of the time way off their max efficiency ranges) this goes way beyond 80%.
That's how EVs work even with the limitations of battery tech.
I am just wondering about the word "rejected". This sounds like energy, the grid is not capable of absorbing, like it is deliberately dumped. But, yeah, looking at the graph in total, it's just waste heat (they might as well have called it that).
@cweickhmann That's what I was going to point out as well. 30% efficiency is considered pretty efficient for fuel cells.
@cweickhmann @Sheril Campus (edu and otherwise) physical plant systems will generate their own energy and use the waste heat for heating or cooling with absorption refrigeration. Sometimes waste heat from during the day charges thermal mass batteries for heating at night or with molten sodium, running steam turbines after the sun is down. Nothing is 100% efficient but localized systems with lots of scavenging do chip away at it and are imo really neat.
@scrottie
That is true. The other way around exists as well: where the gas heater for a medium house is actually a very efficient methane* internal combustion engine with attached generator. The generated electricity is then either consumed on site or fed into the grid.
Still, this stuff is only very recent and has a minor "market share".
*) I just *hate* the term "natural gas" 😜
@Sheril
@cweickhmann @Sheril Yeah, my first reaction was that you can't ignore thermodynamics in this. It puts a limit on efficiency. Also, "rejected" makes no sense here. It's not rejected.
We certainly need cleaner energy though. On a global scale, and fast.