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We need your help to tackle the transport challenge!
Former Community Member
Our aim is not to “drain the ocean” in a few months but to add a voice of engineering insight to the debate, demolish potential myths and legends and suggest some sensible ways forward. We don’t expect to achieve pinpoint accuracy in our investigation, but we can be honest about that. We want to establish some genuine truths and point to where more work or funding should be focussed. We need more information and guidance to existing reliable reports and research on carbon in materials mining and manufacture, infrastructure provision, renewal and maintenance, and end of life recycling. Please share your thoughts by commenting below.
The carbon and resources requirements for additional generating power is difficult to determine. Information like the amount of concrete and steel required and the amount of earth to be moved is easy to find for new Nuclear Power Plants. It is very difficult to find similar information for onshore wind and even harder for offshore wind. With the limited information I could find 3GW of wind, assuming ~30% utilisation required as much concrete as Hinkley Point C. The wind power has an expected life of 20-25 years, Hinkley Point C 60 years plus. Most wind and solar costings are parasitical. The backup and storage problems are left to someone else to deal with/pay for. There is a frequently bandied around figure that wind power pays back the energy used in it’s construction in around a year. I have not found figures to back that up or to confirm what is included. I have to assume that this is measured at the terminals of the wind farm and does not include the transmission and backup/storage installations. The energy payback time for solar PV seems even more dubious, ranging from a few years in southern Spain to probably never in northern latitudes. I currently cannot accept biomass burning as having any green credentials at all. As you say hydrogen is a problem due to the large conversion losses. Blue hydrogen is a waste of resources. You are burning fossil fuel to create the hydrogen and then burning more fossil fuel to capture and store the carbon that is released. Producing hydrogen by electrolysis is inefficient. The numbers I have seen suggest 3 MWh of electricity is required to generate 1 MWh equivalent of hydrogen. There are some interesting comments in this article.
I don’t know if there is a direct, thermal, means of producing hydrogen with nuclear power but to produce it by electrolysis just seems wasteful. Unfortunately most of these ‘green’ ideas assume infinite resources and that these resources can be obtained carbon free. Currently anything you build requires the burning of fossil fuels. To make cement, to make steel, to make copper wires, to refine rare earths all generate emissions. If we try to change too quickly we will actually increase rather than reduce emissions in the short to medium term.
Is it better to run our current systems to the end of their useful lives rather than prematurely scrapping them and wasting the resources invested in them?
Are the 2030 or 2050 targets realistic or even sensible?
The carbon and resources requirements for additional generating power is difficult to determine. Information like the amount of concrete and steel required and the amount of earth to be moved is easy to find for new Nuclear Power Plants. It is very difficult to find similar information for onshore wind and even harder for offshore wind. With the limited information I could find 3GW of wind, assuming ~30% utilisation required as much concrete as Hinkley Point C. The wind power has an expected life of 20-25 years, Hinkley Point C 60 years plus. Most wind and solar costings are parasitical. The backup and storage problems are left to someone else to deal with/pay for. There is a frequently bandied around figure that wind power pays back the energy used in it’s construction in around a year. I have not found figures to back that up or to confirm what is included. I have to assume that this is measured at the terminals of the wind farm and does not include the transmission and backup/storage installations. The energy payback time for solar PV seems even more dubious, ranging from a few years in southern Spain to probably never in northern latitudes. I currently cannot accept biomass burning as having any green credentials at all. As you say hydrogen is a problem due to the large conversion losses. Blue hydrogen is a waste of resources. You are burning fossil fuel to create the hydrogen and then burning more fossil fuel to capture and store the carbon that is released. Producing hydrogen by electrolysis is inefficient. The numbers I have seen suggest 3 MWh of electricity is required to generate 1 MWh equivalent of hydrogen. There are some interesting comments in this article.
I don’t know if there is a direct, thermal, means of producing hydrogen with nuclear power but to produce it by electrolysis just seems wasteful. Unfortunately most of these ‘green’ ideas assume infinite resources and that these resources can be obtained carbon free. Currently anything you build requires the burning of fossil fuels. To make cement, to make steel, to make copper wires, to refine rare earths all generate emissions. If we try to change too quickly we will actually increase rather than reduce emissions in the short to medium term.
Is it better to run our current systems to the end of their useful lives rather than prematurely scrapping them and wasting the resources invested in them?
Are the 2030 or 2050 targets realistic or even sensible?
