In order to create an economy based on this alternate energy provider rather than fossil-fuel based strategies, scientists at the Paul Scherrer Institute PSI have analyzed which regions of the world may make hydrogen most affordably.
One of their findings is that merely switching fossil fuels to electricity and hydrogen wo n’t put an end to greenhouse gas emissions. The research is published in the journal Nature Communications.
Switzerland aims to be climate-neutral by 2050. This implies that no net extra greenhouse gases may be released into the atmosphere starting this year in order to halt climate change. The electricity of transport, economy and communities, while at the same time switching to renewable sources of electricity, such as hydraulic, wind and solar power, is one of the essential building blocks for achieving this goal.
But, power may be employed outside as a supply of energy—for certain applications, its power storage density is inadequate. When higher needs must be satisfied, gas must increase. Aviation, agriculture and the steel industry, for example, indicate applications which may lower their climate impacts by a lot using hydrogen—sometimes more converted to make fertilizer or chemical hydrocarbons.
The researchers collected geographical and economic data and projections to help them analyze the development of a gas business in four different scenarios under the direction of deputy artist Tom Terlouw and project head Christian Bauer from the PSI.
According to their forecasts, the demand for hydrogen will be between 111 and 614 megatons per year in 2050, depending on the situation. In the first scenario, the world continues with business as usual, still relying on fossil fuels. It adheres to the strictest climate protection measures and is able to meet the 1.5 degree target in the fourth and most optimistic scenario. Around 90 megatons of hydrogen are currently produced annually around the world.
Where is there enough space for electrolysis?
Hydrogen can be produced by various processes. Steam methane reforming, in which the element is extracted from natural gas, oil or coal—i. e. fossil fuels—under conditions of high pressure and temperature, is currently the dominant method. In more optimistic scenarios, PEM electrolysers will be increasingly employed instead.
To divide water into hydrogen and oxygen, these devices use electricity and a polymer electrolyte membrane. The process can operate without fossil fuels if only green electricity from renewable sources is used. It produces 90 % less greenhouse gases than steam methane reforming.
The central question, however, was in which parts of the world the hydrogen should be produced using this technology. ” We primarily applied economic criteria”, says Terlouw, “in other words, we looked at where production would be most inexpensive”.
Two things proved crucial: thanks to the abundance of alternative energy sources, such as wind and solar, where can the enormous demand for green electricity needed for electrolysis be met most effectively? Where can the necessary production facilities be built on the required amount of land?
Canada is ideal, Switzerland less so
Large parts of Canada, for example, turned out to be one of the best regions for future hydrogen production. There are many open spaces that are ideal for wind farms, according to Terlouw.
” Despite not giving much thought to these two factors in our study, there is plenty of water around and the political situation is stable.” However, of course, the availability of water for electrolysis also plays a role, as does whether the country concerned is one from which hydrogen can be reliably imported.
Leaving aside these criteria, the central United States also offers good conditions, as do parts of Australia, the Sahara, northern China and northwestern Europe. Because there are both wind and open spaces for building wind turbines and hydrogen factories, either because there is plenty of sunlight for solar energy or because there are both.
Because there are n’t many land available for wind turbines and solar radiation levels are relatively low, Central European industrialized nations like Switzerland or Germany are less suitable for hydrogen production. Other highly populated regions and nations, like Japan or large coastal areas of the US and China, could only produce hydrogen at a comparatively high cost.
We have found a discrepancy between regions with high capacity for hydrogen production and those with low demand, Terlouw says.
A hydrogen economy would need to address this discrepancy through global trade, but doing so requires both political cohesion and additional energy. Ultimately, the energy requirements arise because hydrogen is usually transported as a compound—for example, in the form of ammonia or methanol. The pure gas’s volume is far too large, while the much smaller liquid form requires a lot of cooling.
The ecological downsides of green hydrogen
Additionally, the study examines other potential hydrogen economy environmental effects, which are frequently overlooked by the general public. First of all, it is crucial to emphasize that even a functioning hydrogen economy will continue to generate residual greenhouse gas emissions, Terlouw says.
According to the study, these residual emissions amount to almost one gigaton of annual equivalent CO2. Total emissions are currently around 40 gigatons. ” It will not be possible to reduce the climate impact to zero”, Bauer confirms.
This is primarily because emissions are directly related to the production and distribution of hydrogen.
On the one hand, leaks are estimated to release 2.5 % of the hydrogen into the atmosphere, which indirectly serves as a greenhouse gas by promoting the formation of potent greenhouse gases like methane and ozone.
On the other hand, electrolysis systems exhibit so-called embodied emissions, which occur during the production and transport of the required materials, even if the final systems run on green electricity.
According to Terlouw, “many of the systems and machines used in a hydrogen economy are produced in nations where their production will largely depend on fossil fuels for the foreseeable future.” ” Most solar panels come from China nowadays, for example, where the bulk of the electricity is still produced by coal-fired power stations”.
Anyone who wants to achieve climate neutrality must make up for these residual emissions by capturing and removing equivalent amounts of carbon dioxide from the atmosphere. Technologies such as direct air capture, in which special equipment removes CO2 from the air, could be used for this purpose. Or reforestation, where planting more trees binds particular amounts of carbon from the air.
Critical materials
Beyond its impact on our climate, Terlouw and Bauer believe that other environmental effects of a hydrogen economy should also be taken into account. The machines and systems employ a variety of materials that are either produced in a manner that is either harmful to the environment or that are.
For instance, wind turbines have permanent magnets made of rare earth metals whose extraction in China does not conform to European environmental standards. Iridium, a metal that is regarded as problematic simply because it is so uncommon, serves as the catalyst for PEM electrolysis. Additionally, the large land and water needed to produce hydrogen may also be a harmful environmental factor.
” Last but not least, there is the big issue of social acceptance”, as Terlouw points out. Will people accept, for instance, that large hydrogen production plants are occupying coastal landscapes? In water-scarce areas, before being electrolyzed, seawater would first have to be desalinated, which requires additional energy and land.
” In the current study, we have not yet taken such factors into account”, admits Bauer. ” Further studies are to follow. We want to highlight the potential ways to achieve the energy transition. Whether we go on to pursue them, and how rigorously we do, is ultimately a socio-political question”.
Citation: Large parts of Canada are ideal for upcoming gas production, worldwide analysis suggests (2024, August 16) retrieved 16 August 2024 from
This document is subject to copyright. No part may be reproduced without the written permission of any fair dealing made for the purpose of private study or research. The content is only provided for informational purposes.
