Hybrid Cars

The release of carbon dioxide (CO₂) is not a new phenomenon as it has always been emitted naturally through the carbon cycle. However, since the industrial revolution carbon dioxide levels have greatly increased, most probably due to human activities, and global atmospheric concentrations are now 35% higher than they were before the industrial revolution (EPA 2010). In the UK today, 29% of carbon emissions come from transport and 70% of that derives from road transport (Carbon Trust 2010). Therefore, it would appear logical to try to cut carbon dioxide emissions from the road transport sector.

There are obvious lifestyle changes that we can all incorporate, such as using public transport more often and combining journeys so that we take fewer. However, it is inevitable that we still have to make journeys in our cars, whether for business or pleasure Therefore, are there more environmentally friendly cars out there that we could choose to drive?

Car manufacturers have responded to the bad press that they have received over the years in relation to carbon dioxide emissions and the contribution they make towards the greenhouse effect and have developed a range of new types of engines. Along with electric cars, high efficiency internal combustion engines and fuel cell cars are hybrid cars. A simple explanation of a hybrid car is that it recovers the heat energy that is normally lost from the action of braking and uses this heat energy to power the car for acceleration (Carbon Trust 2010). The energy that is needed to drive the car is derived from at least two different sources and currently most hybrid cars gain their energy from thermal engines (petrol or diesel) and electricity.

Four types of hybrid cars

Micro Hybrid – this car has a thermal engine with some of its function, such as starting the car, powered by battery.
Mild Hybrid – this car works by using the same technology as the micro hybrid but it stores the kinetic energy generated when breaking and uses it for acceleration. Therefore it is more powerful.
Parallel Hybrid- this has a thermal engine and an electric engine. At low speeds the car can switch to using its electric engine and it recovers the kinetic energy produced when braking.
Hybrid Series – this car has a generator run on petrol that provides energy for the electric motor. During braking, the batteries are re-charged.

Advantages of Hybrid Cars

Hybrids consume less petrol or diesel, therefore saving money (especially significant as fuel prices seem to continuously rise).
Reduction in consumption of fuel by 10-50%.
Reduced production of harmful greenhouse gases such as carbon dioxide.
Reduced vehicle noise.
Huge savings when driving in urban areas as car speeds are generally lower; making it possible to use solely the electric part of the hybrid engine. Adds to the improvement of air quality.
Incentives to buy, such as reduced taxes.
Hybrid cars can be more expensive to buy initially but are more economical in the long term due to lower running costs.

A few examples of Hybrid cars