Lupfe's innovation aims to increase EHPS engine's power-to-weight ratio and reduce fuel consumption at fair maintenance cost.
The engine's advanced thermal and gas-exchange processes provide outstanding fuel economy. In the eVTOL category up to 750 kg of MTOW, compared to turbine-based hybrid solutions, 45 - 100 % less fuel is needed for flight, based on which turbine engine is in question.
This difference in fuel consumption roughly translates to 40 - 80 kg less weight at 2 hours flight time and 60 – 160 kg less weight at 4 hours flight time, considering fuel consumptions and ready to use weights of hybrid propulsion systems. Comparisons were made at 80 kW to 140 kW range of continuous power.
Increased flight range
The hourly 10 - 40 kg less fuel consumption also translates into longer flight range. At the same take-off weight, the range can be increased by 2 - 2.5 hours.
Where the difference of fuel consumption is lesser ( 10-15 kg/hour ), there the ready to use weight of turbine-based hybrid systems is 30-35 kg greater. This is the weight of the extra heat exchanger, also known as recuperator that improves fuel economy at turbines but deteriorates power-to-weight ratio.
More flexible payload-range balancing
Extremes of payload-range ratio are improved, therefore a more agile mission planning is available.
Increased cargo space
The less weight of the required fuel also means lower volume. The difference in fuel volume could be 15 to 60 liter/hour. A certain cargo drone could have a subtype with extended cargo space without any significant modification of the airframe or newly designed drones could also have this advantage.
Economies of infrastructural investments
A more dispersed fuel station coverage can be sufficient due to the 2 times longer flight range. Infrastructure costs can be lower for developing new networks and increasing density of existing networks.
Increased time savings for time sensitive shipments
Aircrafts need less fuel stops, therefore remain airborne longer. Less off-route time and less station dwell time (by occasions) needed for operation. This increased freedom for route planning can result significant advantage in time sensitive shipments. Increasing density of deliveries with the same aircraft is easier.
Less harmful environmental impact, significantly lower CO2 emission
The superior fuel consumption provides significant advantage in CO2 emission. The difference in specific CO2 emission varies from 250 to 860 gCO2/kWh, depending on which turbine-based hybrid electric system is in question. Depending on operation power and yearly exploit of aircrafts, this roughly translates to 30 - 170 tonCO2 savings per aircraft at 255 day/year and 6 hours/day flight scenario. (Power in analyses between 80 - 140 kW range)
Lower sensitivity to fuel price increase
In the economic environment where fuel prices are increasing, Lupfe's hybrid system provides lower exposure for the operator, that might additionally occur as advantage against the competing eVTOL airplanes in express logistics.
Multicopter airframes with Lupfe's system can compete in terms of operating costs with other more efficient airframes that use turbine-based hybrid solutions.
Easier to keep the MTOW under 750 kg while range and payload are increased.