alternative energy sources that use the natural power of the wind, waves and sun are too expensive and complicated to replace the coal ,oil and gas that we use to power our cities and transport. To what extent do you agree or disagree with this option?

It is a heated debate that the

sources

of renewable

energy

,

such

as wind, seawater, and sunlight are costly and ineffective to replace the

non-renewable

energy

that has been widely used in our daily lives. In my opinion, I mostly agree with the statement and there are some detrimental flaws of renewable

energy

, even though it might bring environmental benefits to the cities. Indeed, it is environmentally-friendy when we consume more renewable

energy

. As we all know, the overconsumption of coal and gas has caused serious air pollution in a variety of cities, due to the large emission of carbon dioxide.

However

, power generated by the nature can effectively reduce the emission of carbon dioxide and

hence

the environment can be well protected.

Also

,

non-renewable

energy

will be used up one day, which may lead to a serious problem of

energy

shortage around the globe.

For instance

, coal is formed from dead bodies of ancient animals million years ago. The

sources

of coal are rigid and cannot be increased easily.

On the contrary

, the

sources

of renewable

energy

such

as wind, seawater and sunlight are gifts from nature and the supply is not scarce. Sadly, we should not neglect the problems faced by the renewable

energy

supply in nowadays society.

First

of all, the set-up cost for the infrastructures of renewable

energy

is significantly higher than that of

non-renewable

energy

.

For instance

, it costs almost a hundred million Hong Kong dollars to build a small wind turbine farm on Yap Lek Island, while a big coal supply factory can be set up at a much lower expense. Other than that, the feasibility of the renewable

energy

supply is low.

In other words

, not every city is a perfect place to widely adopt renewable

energy

use

.

For example

, the harbours near Hong Kong do not have big waves and

therefore

it is not an ideal place for the common

use

of seawater

energy

.

Thirdly

, the sophisticated generation system of renewable

energy

has low efficiency in generating power

use

, especially when it is compared with the

use

of

non-renewable

energy

.

For example

, only 6% of power is generated by eco-friendly

energy

sources

, while over 80% of it is from

non-renewable

energy

. In conclusion, I do think that the

sources

of renewable

energy

are worth establishing as they can safeguard the ecosystem, but there are a lot of obstacles that are waiting to be tackled,

such

as the high financial cost, geographical limitations and low efficiency.