by Global Witness, Sept 1, 2022
Hydrogen could be an important part of the renewable energy transition, but not if the fossil fuel industry has its way.
At first glance, hydrogen seems to be the perfect solution to our energy needs. It doesn’t produce any carbon dioxide when used. It can store energy for long periods of time. It doesn’t leave behind hazardous waste materials, like nuclear does. And it doesn’t require large swathes of land to be flooded, like hydroelectricity.
All in all, hydrogen seems too good to be true. No wonder the energy industry is currently pushing hydrogen as the fuel of the future. So…what’s the catch?
Not all hydrogen is created equal
While it’s true that hydrogen is carbon-free at the point of use, this only tells part of the story. Before we get to the stage where hydrogen is used, it first needs to be produced. And it’s this process where the complications begin.
There are several different ways of producing hydrogen, with varying levels of carbon intensity. One is to pass an electric current through water, splitting the water molecules apart into their constituent hydrogen and oxygen atoms. With this method, the key is what kind of electricity you’re using to create the electric current. If the electricity is from renewable sources, then the overall process will be effectively carbon free. If you’re using electricity generated by burning fossil fuels, then the hydrogen will be very carbon intensive.
by K.G. Gregory, Aug 23, 2022 in FriendsOfScience
Many governments have made promises to reduce greenhouse gas emissions by replacing fossil fuels with solar and wind generated electricity and to electrify the economy. A report by Thomas Tanton estimates a capital cost of US$36.4 trillion for the U.S.A. economy to meet net zero emissions using wind and solar power. This study identifies several errors in the Tanton report and provides new capital cost estimates using 2019 and 2020 hourly electricity generation data rather than using annual average conditions as was done in the Tanton report. This study finds that the battery costs for replacing all current fossil fuel fired electricity with wind and solar generated electricity, using 2020 electricity data, is 111 times that estimated by the Tanton report. The total capital cost of electrification is herein estimated, using 2020 data, at US$290 trillion, or 13.5 times the U.S.A. 2019 gross domestic product. Overbuilding the solar plus wind capacity by 18% reduces overall costs by 17% by reducing battery storage costs. Allowing fossil fuels with carbon capture and storage to provide 60% of the electricity demand dramatically reduces the total costs from US$290 trillion to US$20.5 trillion, which is a reduction of 92.9%. Battery storage costs are highly dependent on the year’s weather and the seasonal shape of electricity demand.
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