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What is net zero and why is it necessary?
Former Community Member
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Simon, As you say the concept is simple, it is the implementation, especially in the current expected time frames that is difficult. What techniques do we have to absorb CO2?
1) Plant trees. This works but on a decade time scale. Bigger trees obviously absorb more CO2 than saplings.
2) Capture and store CO2 from flue systems. A few pilots exist but they are all energy intensive. Our local Refuse Incinerator has an experimental CO2 capture/concentration system. The CO2 is then piped to some nearby greenhouses (which are also heated with waste low grade heat from the incinerator) to enhance the growth of the plants. Does it work, yes. Does it make any sense financially or in the total energy balance, probably not.
3) Capture CO2 from the air and store it. Very energy intensive due to the low concentration compared to flue gas. Will it ever achieve a positive balance?
4) ???
Suppose I want to erect a wind turbine to power my hospital (2MW?). I will probably need a 6MW turbine given a 30% capacity factor. I will ignore energy storage for the moment, SEP (Somebody Else’s Problem).
What do I need for this? (All guesstimates) 1000 tonnes of concrete for the base. 300 tonnes of steel for the tower, housing, etc. 50 tonnes of oil based products for the composite blades, lubricants, seals, cable insulation, paint, etc. We will still need an oil and petrochemical industry. 10 tonnes of copper for the generator and connecting cables. All sorts of materials for the magnets, inverters etc.
I will emit a significant quantity of CO2 in making these materials and assembling them into a working turbine. What do I do about this CO2? If I plant an appropriate number of trees they won’t have absorbed the CO2 for a couple of decades so I have contributed to a net increase for a period of time.
I can say that I have stopped fossil fuels being burnt to generate this electricity which doesn’t reduce the amount of CO2 I have released by building my turbine but reduces future emissions. Once again this takes time.
When can I say that I am ‘Carbon Neutral/Net Zero’ according to your criteria?
Now add more energy and materials for some energy storage to keep the ICU running when the wind stops. When do reach ‘Carbon Neutral/Net Zero’ now. Is it a useful or even sensible criteria?
Simon, As you say the concept is simple, it is the implementation, especially in the current expected time frames that is difficult. What techniques do we have to absorb CO2?
1) Plant trees. This works but on a decade time scale. Bigger trees obviously absorb more CO2 than saplings.
2) Capture and store CO2 from flue systems. A few pilots exist but they are all energy intensive. Our local Refuse Incinerator has an experimental CO2 capture/concentration system. The CO2 is then piped to some nearby greenhouses (which are also heated with waste low grade heat from the incinerator) to enhance the growth of the plants. Does it work, yes. Does it make any sense financially or in the total energy balance, probably not.
3) Capture CO2 from the air and store it. Very energy intensive due to the low concentration compared to flue gas. Will it ever achieve a positive balance?
4) ???
Suppose I want to erect a wind turbine to power my hospital (2MW?). I will probably need a 6MW turbine given a 30% capacity factor. I will ignore energy storage for the moment, SEP (Somebody Else’s Problem).
What do I need for this? (All guesstimates) 1000 tonnes of concrete for the base. 300 tonnes of steel for the tower, housing, etc. 50 tonnes of oil based products for the composite blades, lubricants, seals, cable insulation, paint, etc. We will still need an oil and petrochemical industry. 10 tonnes of copper for the generator and connecting cables. All sorts of materials for the magnets, inverters etc.
I will emit a significant quantity of CO2 in making these materials and assembling them into a working turbine. What do I do about this CO2? If I plant an appropriate number of trees they won’t have absorbed the CO2 for a couple of decades so I have contributed to a net increase for a period of time.
I can say that I have stopped fossil fuels being burnt to generate this electricity which doesn’t reduce the amount of CO2 I have released by building my turbine but reduces future emissions. Once again this takes time.
When can I say that I am ‘Carbon Neutral/Net Zero’ according to your criteria?
Now add more energy and materials for some energy storage to keep the ICU running when the wind stops. When do reach ‘Carbon Neutral/Net Zero’ now. Is it a useful or even sensible criteria?
