Original Article All-electric propulsion for future business jet aircraft: A feasibility study Borys Lukasik and Witold Wisniowski Abstract The main goal of this paper is to investigate feasibility of using all-electric propulsion system for a mid-light business jet aircraft in the near future (20–30 years from now). The secondary goal is to assess the impact of using such system on operating costs and emission reduction. This paper presents calculations of business jet aircraft mission energy demands and compares them with batteries capabilities. Three different types of lithium batteries are investigated in terms of their energy densities projected for three different time frames. Mass of batteries that is required to provide demanded amount of energy to perform the mission is compared with the maximum mass of fuel that the baseline aircraft is able to take. On this basis, the feasibility of all-electric propulsion system is assessed. Additionally, in order to show the limitations of such system, maximum range is calculated for the mass of batteries that would potentially enable to perform the flight. Furthermore, CO 2 and NOx emission of the baseline aircraft engines are compared with the amount of gaseous pollutants which are emitted by the power plant, when energy needed to recharge batteries is being produced. Finally, the potential fuel cost reduction is calculated based on the cost of electricity that would be used to recharge batteries. Keywords All-electric propulsion, emission reduction, more electric aircraft, operating costs reduction, propulsion systems Date received: 3 March 2017; accepted: 9 July 2017 Introduction Currently existing airplanes with all-electric propulsion are typically small (two to four seat) gen- eral aviation or motor glider class designs. They offer no emission during the flight, lower operating costs (related to fuel) and reduce noise. However, their per- formance shows that this type of aircraft suffers a lot from the low cruise speed, as well as limited range and flight endurance, due to the low energy density (energy stored per unit mass) of currently available electric energy storage means (mainly batteries, but also flywheels, supercapacitors and others) 1 in com- parison to the energy density levels of hydrocarbon fuels. Moreover, their purchase price is comparable, or higher than the price of the same class airplanes with standard internal combustion engines (ICEs); therefore, there is still very low demand for this type of aircraft on the market. Yet, one needs to recognize that most of the existing airplanes with all-electric propulsion system are typical technology demonstra- tors (e.g. Taurus G4, 2 e-Genius 3 or Airbus E-Fan 4 ) which are meant to draw the path forward for signifi- cantly more energy-efficient commercial aircraft of the future. In all three cases, acquired experience shows that the right way is to use electric systems in combination with ICE. The best proofs of that are the already designed development versions of mentioned airplanes, which utilize hybrid propulsion: e-Genius hybrid, 3 ECO 4 (see literature 3,5 ), Airbus E-Fan Plus 4 and Pipistrel Panthera hybrid. 6 However, some sources 1,7 anticipate that the potential battery energy density that will be feasible in the near future (20–30 years from now) can be three to six times bigger than the energy density of currently available, state-of-the-art batteries which is, in aver- age, about 200–250 Wh/kg (80–200 Wh/kg for lithium-ion batteries, 250–300 Wh/kg for lithium-sul- phur batteries and 300–350 for lithium-air batteries). 1 As the batteries technology advances, aircraft with all- electric propulsion will have the potential to meet the Small Air Transport (SAT) Aircraft Family Program requirements and be the low-cost, no emission, com- muter airplanes. 8 Also, some other research 9 shows Proc IMechE Part G: J Aerospace Engineering 2017, Vol. 231(12) 2203–2213 ! IMechE 2017 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0954410017727027 journals.sagepub.com/home/pig Institute of Aviation, Warsaw, Poland Corresponding author: Borys Lukasik, Institute of Aviation, al. Krakowska 110/114, Warsaw, Mazowieckie 02-256, Poland. Email: borys.lukasik@ilot.edu.pl