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As biomass is the only source of fuel for us biological machines, I don’t think anyone is questioning it in regards to food. But biomass being converted into e

As biomass is the only source of fuel for us biological machines, I don’t think anyone is questioning it in regards to food. But biomass being converted into electricity is horribly inefficient.

beefield 4y ago
> But biomass being converted into electricity is horribly inefficient Even in CHP?
- dinkleberg 4y ago
  The thing you need to consider with biomass is the efficiency of photosynthesis, which is incredibly poor. The upper limit for most plants is like 2% efficiency, many are significantly worse than that. Whereas photovoltaic cells are much higher, ranging from 15-20% or even higher. And this continues to improve. And that optimistic 2% efficiency for plants is just the energy conversion to grow the actual plants. Then to convert it into electricity requires it to go through a power plant which often have lower efficiencies of say 30%. If it is in a co-generation facility, it may have upwards of say 80%. Which sounds nice, but when you multiply those efficiencies and end up with in the best case, something like 1.6% efficiency which is terrible. And that is to ignore the other major factor which is that burning biomass causes major pollution. Fossil fuels are just convenient biomass that have been given the luxury of hundreds of millions of years to compress into dense hydrocarbons which make a convenient fuel source. We don't have this luxury when it comes to creating new biomass. The best aspect of biomass is that it is freely available to everyone. Anyone can gather sticks to burn. However, the parts of the world that still heavily rely on these methods for heating their homes and are used for cooking unfortunately suffer the consequences of breathing all of the smoke in over the years.
ZeroGravitas 4y ago
The phrase "biomass" is misleadingly vague. The article is aboit dedicated biomass for electricity production, which given the cheapness of solar and wind is a little like dunking on steam-powered cars. I'm not aware of anyone arguing for that as an approach. We did these sums a couple of decades ago. On the other hand, wwste food, sewage, manure, and various other things that would become methane are useful to capture as it can be GHG negative comparrd woth letting it rot. That is also "biomass".

As biomass is the only source of fuel for us biological machines, I don’t think anyone is questioning it in regards to food. But biomass being converted into electricity is horribly inefficient.

beefield 4y ago

> But biomass being converted into electricity is horribly inefficient Even in CHP?

dinkleberg 4y ago
The thing you need to consider with biomass is the efficiency of photosynthesis, which is incredibly poor. The upper limit for most plants is like 2% efficiency, many are significantly worse than that. Whereas photovoltaic cells are much higher, ranging from 15-20% or even higher. And this continues to improve. And that optimistic 2% efficiency for plants is just the energy conversion to grow the actual plants. Then to convert it into electricity requires it to go through a power plant which often have lower efficiencies of say 30%. If it is in a co-generation facility, it may have upwards of say 80%. Which sounds nice, but when you multiply those efficiencies and end up with in the best case, something like 1.6% efficiency which is terrible. And that is to ignore the other major factor which is that burning biomass causes major pollution. Fossil fuels are just convenient biomass that have been given the luxury of hundreds of millions of years to compress into dense hydrocarbons which make a convenient fuel source. We don't have this luxury when it comes to creating new biomass. The best aspect of biomass is that it is freely available to everyone. Anyone can gather sticks to burn. However, the parts of the world that still heavily rely on these methods for heating their homes and are used for cooking unfortunately suffer the consequences of breathing all of the smoke in over the years.

ZeroGravitas 4y ago

The phrase "biomass" is misleadingly vague. The article is aboit dedicated biomass for electricity production, which given the cheapness of solar and wind is a little like dunking on steam-powered cars. I'm not aware of anyone arguing for that as an approach. We did these sums a couple of decades ago. On the other hand, wwste food, sewage, manure, and various other things that would become methane are useful to capture as it can be GHG negative comparrd woth letting it rot. That is also "biomass".