ENERGIA
Esperanças na energia do hidrogénio
September 5, 2023 -
Uma vila litoral do nordeste de Inglaterra será a primeira “aldeia de
hidrogénio” do RU, passando do gás natural ao hidrogénio verde no âmbito de um plano para chegar a emissões zero até 2050.
The British government wants to phase out natural gas boilers by 2035. The proposal will replace natural gas (methane) with hydrogen as an energy source in residential and commercial buildings -- hydrogen combustion does not produce carbon dioxide, a significant player in global warming.
However, hydrogen, with its much lower ignition point, is inherently less safe than natural gas and produces more harmful nitrogen oxide (NOx) than natural gas. To demonstrate comparable risk, Hy4Heat conducted a quantified risk assessment (QRA), performing 120 tests to establish the relative safety of hydrogen compared to natural gas within a domestic property.
Potential ignition risks include hot surfaces, electrical contacts, and electrical motors.
The QRA, undertaken by Arup, concluded that there will be many more fire and explosion events with 100% hydrogen -- 39 per year compared with nine for natural gas. Furthermore, the overall risk of injury will soar to 65 for hydrogen compared to 17 for natural gas.
HyDeploy, an earlier six-year QRA that started in 2017, injected 20% hydrogen by volume into three live gas networks.
HyDeploy found that current appliances and gas networks can adopt a 20% hydrogen blend without modification. With no exceptions, HyDeploy found every natural gas appliance was safe and leak-tight on 20% hydrogen-blended natural gas.