Accelerated Transition to CO2 Neutrality—Energy Carriers and Powertrain Technologies

Abstract:

Due to the ambitious climate protection targets of the ‘Paris Agreement’ （2050） and China （2060） and the pursuit of energy independency， an increased technology-independent research and development of energy efficient and CO₂ neutralization methods is needed^［1-2］. Basically， there are three main powertrain concepts for vehicles available： battery electric drive， fuel cell powered electrical drive， and CO₂ neutral sustainable synthetic fuel powered combustion engines. A simplified subsumption of efficiency factors along the process chain from cradle to grave as decision factor does not reflect the most efficient reduction of CO₂ emissions and reduction of fossil energy demand over the timeline. Due to regional limited availability of renewable energy compared to necessary energy supply， a lot of technical and infrastructural problems must be solved in a cost-efficient way in order to enable this large-scale substitution of fossil energy. In addition to the direct use of renewable electricity， green hydrogen and derived synthetic fuels are unique enablers to accelerate the substitution of fossil energy significantly. Synthetic fuels can be implemented short-term and worldwide for the whole existing vehicle fleet （approx. 1，2 billion vehicles） by utilization of the installed energy logistics. The "drop-in" rate can be successively increased （blending of gasoline， diesel， or natural gas） until complete substitution by green hydrogen， synthetic fuels， or direct use of electricity. This paper is presenting both hydrogen powertrains （H₂ combustion engine and fuel cell powertrain） and synthetic fuels， and technical solutions therefor.

Key words:internal-combustion engine;synthetic fuels;methanol;hydrogen power system