Electricity + Control March 2018

ENERGY MANAGEMENT + ENVIRONMENTAL ENGINEERING

Sustainable Energy And Electrifying the Transport Sector Carel Snyman, Energy Consultant

Burning something to release the energy it contains and then using this energy to do work will never be sustainable.

T ypically the world’s fossil resereves are be- ing taken from the ground and used directly as primary energy fuel or are converted via chemical processes into secondary energy carriers such as liquid fuels before being combusted to re- lease energy to produce heat. This then to be used as is or to be set alight in order to produce electric- ity or motion. The burning process removes oxygen from the air and releases harmful gaseous emis- sions that poison the air people breathe and con- taminate the environment as well as contribute to global climate change. Not only are these combus- tion processes harmful, they are aslo very wasteful in converting energy into work. Most of the waste is in the form of heat. Today this behaviour should be regarded as outdated and maybe even criminal. At least 25% of all world energy is used for trans- port. This is increasing steadily as the population and congestion increases. Alternative sources of energy have been identified and their uses have World Energy Consumption by Sector 2012 (EIA Data) Industrial Transportation

been demonstrated. These are renewable energy sources effected by the sun – solar, wind, geother- mal and biomass. Solar and wind energy being the most attractive due to their fast reducing cost of installation, long operating life with low main- tenance requirements and ease of access. Most important though is the fact that we will not 'run out' of these resources and that the use of these energies does not cause any harm to people nor to our environment. Transport sector The biggest challenge in the transport sector is clearly the vast and increasing quantities of ex- haust emissions released by millions of exhaust pipes of road going cars and trucks stuck in slow moving traffic in city areas. It seems safe to say that at least 80% of all energy used in the trans- port sector is being consumed by road vehicles. Air and water transport being much smaller cuts of the transport energy consumption pie chart. Rail transport to a large extent has already been electrified – the higher torque and efficiency of the electric motor providing a significant advan- tage compared to diesel engines. Being confined to fixed routes the supply of energy to the motor to do the mobility work is also simple to do and convenient. The focus for improvement then should be on road vehicles. In SA light road vehicles consume about 65% (mainly passengers) of all transport en- ergy supply and big road trucks about 22% (mainly freight). Should the energy supply to the transport sector change from liquid fuels to electricity, the

Take Note!

Electric transport makes sense. We should look at sup- porting our own energy generation instead of importing our energy to power our transport sector. South Africa is in a po- sition to benefit – more than most countries – by supplying our mobility energy needs with re- newable energy.

1

2

3

Residential Commercial

46 Electricity + Control

MARCH 2018