HYDROGEN
Future Environmental Impacts of Renewable Hydrogen Production in the Netherlands
BY G . Z . Makashova , J . M . M . Bruijnen , Ch . McWhinney , A - W . T . Niehof .
In order to meet the aim , set in the Paris Agreement to limit global warming below 2 ° C , a massive decarbonization of all energy-intensive sectors is required . Hydrogen is considered to be an alternative to reduce traditional fossil fuel use . However , the role of hydrogen as a part of the energy transition has yet to be assessed from an environmental impact loop .
Left : Gaukhar Makashova , INERC & John Bruijnen , INERC
The Netherlands plans to create a renewable energy hub with its own production of renewable hydrogen . The hydrogen produced would be used for transportation purposes ( e . g ., forklifts , cars , ships ), for monitoring and gathering information using hydrogen powered unmanned aerial vehicles ( UAV ), and to reduce the generation capacity of the local power grid . From this perspective , the Alkaline Water Electrolysis ( AWE ) offers the potential for renewable hydrogen production in the future . Solar and wind energy are suitable renewable power sources for hydrogen production through water electrolysis due to their advantages to be deployed decentralized . Nevertheless , this type of renewable energy-based electrolysis is still at a pilot scale and a detailed environmental performance is needed .
How sustainable is renewable hydrogen production ?
By 2050 the larger quantities of hydrogen including different types of usage ( e . g ., ships , harbour trucks , forklift trucks ) plans to be deployed with the capacity of 1 MW of produced hydrogen . Three future electricity scenarios have been considered for the hydrogen production : ( a ) 2030 with fossil fuels in electricity share ( 2030 ), ( b ) 2050 with green methane ( based on carbon capture and storage technologies ) ( 2050 ) and ( c ) 2050 based on fully renewable electricity sources ( 2050 RES ) [ 1-3 ]. They have been compared with the current situation ( current ) ( Figure 1 ).
Using the prospective Life-Cycle Analysis the potential environmental impacts associated with the production of hydrogen by an AWE under these three future energy scenarios were
Figure 1 . Electricity mix scenario ’ s in the Netherlands .
evaluated . The results show that when using the current electricity mix , the climate change impact category indicating the greenhouse gas emissions is equal to 12.2 kg CO 2 eq . for each kg of produced hydrogen ( Figure 2 ). This amount is reduced by 80 % if the electricity required by the system is generated 100 % from renewable sources in 2050 . In this case , the production of 1 kg of hydrogen causes the emission of 2.69 kg of CO 2 equivalent .
The reduction in the share of natural gas in the electricity supply from 37 % in 2023 to 18 % in 2030 and to 0 % in the 2050 and 2050 RES scenarios is one of the main reasons for the decrease of the CO 2
-eq ( see Figure 2 ). The production of green methane in 2050 means that the Carbon Capture and Storage ( CCS ) technologies would apply . During the CCS about 72 % of the CO 2 would be captured and placed to the storage facilities . Therefore , the
CO 2
-eq . decrease sharply in 2050 scenario resulting to 1.2 kg CO 2 eq . per 1 kg of H 2
. The higher values of GHG in the fully renewable scenario are due to the expansion of solar PV energy in order to produce 1 MW of renewable hydrogen .
Figure 3 ( across page ) shows the relative indicator results for other impact categories . In general , a shift from the grid electricity to electricity from wind turbines and PV solar panels results in a reduction in almost all impact categories except carcinogenicity and freshwater ecotoxicity .
Carcinogenicity indicates the potential estimated rise of disease cases per kg of a substance emitted . Freshwater ecotoxicity measures the toxic effect on freshwater aquatic species in the aquatic ecosystems . The main reason for the increase in both indicators is the expansion of solar PV in electricity production . The manufacturing of solar PV involves mining , extraction and purification processes that use carcinogenic , flammable , corrosive , toxic compounds ( e . g ., hydrochloric acid , nitric acid , isopropanol , ammonia , and selenium hydride ). Moreover , a significant amount of water is required to produce solar PV . For example , the water consumption during silicon production is around 180 kg water per 1 kg of silicon , and
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Figure 2 . Climate change impact category of the AWE system for hydrogen production in future energy scenarios .