What is the difference between a series hybrid and a parallel hybrid? What about light hybrid and downloadable hybrid? And how far, for example, with 20 kilowatt hours charged in the battery, can you imagine going?

Tuukka Heikkilä, M.Sc. in Electrical Engineering and expert in the Finnish Energy Industry Association, Kari Kaihonen, Chairman of SATL and Development Director of Taitotalo, Vesa Linja-aho, Metropolia's Automotive Electronics Lecturer, Frans Malmari Diagniko the experts clarify the relevant basics with their car types as follows:

Fully Electric Car

In a fully electric car, only electricity is used for energy. Electricity is charged to the car battery and the electric motor uses the energy stored in the battery. The electric energy charged to the car can be produced by various methods, such as solar and wind power, biogas or natural gas, nuclear power or coal. The battery capacity is typically 30 to 100 kWh and the electric distance is 150 to 500 km.

Downloadable hybrid

The rechargeable hybrid can be charged and driven like an electric car, but it also has an internal combustion engine that can generate electricity or directly mechanically propel the wheels. The battery life is usually smaller than in all-electric cars and a small engine would also suffice as an internal combustion engine. The battery capacity is typically 5 to 20 kWh and the electric distance is 20 to 100 km.

Hybrid, light hybrid and self-loading hybrid

In the hybrid, the battery cannot be charged externally, i.e. the energy source is fuel. The battery is quite small and is always charged with electrical energy produced by an internal combustion engine. The car therefore charges the battery itself by rotating the generator with an internal combustion engine. The electric motor can travel short distances and when decelerated, the batteries can be charged with kinetic energy, such as in an electric car or a rechargeable hybrid. The technology can reduce fuel consumption and emissions. The battery capacity is typically 1 to 3 kWh and the electric distance is 5 to 10 km. A light hybrid is a subtype of hybrid in which the electric motor used is small and does not drive the car alone, but only supports the internal combustion engine and utilizes kinetic energy in decelerations.

Serial hybrid and parallel hybrid

All hybrids have two energy sources. In a parallel hybrid, they produce power in parallel. The internal combustion engine rotates the direct wheels and the driving force that moves the car through the transmission. The same goes for the electric motor. They can operate separately or simultaneously. The technology is suitable for rechargeable, self-charging and light hybrid. In a series hybrid, they produce power connected in series, i.e. in series. An internal combustion engine drives a generator that produces electricity for an electric motor that produces the driving force that moves the car. This solution requires a separate generator or two electric motors, one of which is used as a generator. In several series hybrids, the electric and internal combustion engines can be connected both in series and in parallel. The technology is mainly used in rechargeable and self-recharging hybrids.

You can find more of this set of electric car questions to be solved with their answers in the links below. Source of answer: Finnish Automobile Technology Association (2020): Questions about electric cars - SATL experts answer.