With so much concern for global warming, there is much debate about what the best sources of energy are for countering the rising temperatures. Here I will cover a couple of important considerations, which will hopefully make it obvious which are the best sources.
The most important consideration is whether the energy is readily available or needs to be released from a stored state.
The first problem with stored energy is that upon release, it adds energy to the environment, which, in the context of trying to reduce global temperatures, is counter-productive. Typical stored sources used to produce power are fossil fuels and nuclear. Heavy reliance upon these just adds substantial heat to the atmosphere.
Of course, these stored energy sources have another downside in that they are polluting, with fossil fuels contributing to carbon dioxide buildup, leading to further warming, and nuclear leaving highly dangerous radioactive products that we still don't know how to neutralise, thus dumping the problem on future generations.
Already released sources are sunlight, wind and water. The clear advantage of them is that the earth's ecosystems have already adapted to them, and importantly that adaptation has enabled us to exist and to thrive.
The closeness of the usage of the energy to its source is also important, as there can be adverse effects depending upon the source.
The main factor favouring local sources is the much lower infrastructure requirements and thus its cost savings for society. The general downside of having distance is that the energy released at the high-intensity generation locale is dumped into the atmosphere at the usage locale, which can create temperature-related effects upon the atmosphere there, such as temperature-inversion in Melbourne, Australia. Also, mass generation sites tend to be rather unsightly, and so typically need to be positioned well away from where people live.
Obviously, polluting sources are best situated far from where they are used by people. Unfortunately, that requires transmission of the power, incurring increasing losses and risk of line failure the further the distance. Conversely, local generation and usage can bring better coupling between them, minimised losses, and constraint of failure risks to its few users.
The other advantage of local generation is that the local ecosystem is less likely to be adversly affected. For example, sunlight normally falls on the ground, heating it up during the day, and releasing into the evening. With solar panels, the panels capture the energy instead, and coupled with storage, like batteries, heatbanks or water towers, is released for usage into the evening. Both scenarios have the same local absoption and release scenario, resulting in minimal effect upon the local environment.
To be really effective, energy generation needs to be coupled to some form of storage, as that allows autonomous operation, and minimises system size as peaks can be supplied from storage, rather than building to handle maximum peaks.
For electricity, batteries have rapidly become economically feasible. However, they require a lot of energy to manufacture, use a lot of toxic compounds, and have limited life. Using automated cranes and concrete blocks has proved successful with high efficiency, with the advantage of being able to be put anywhere, unlike hydro-power. For heat, heat-banks can store energy for later release.
With these considerations, we are now in a position to rank sources as to their suitability to counter global warming.
|1||Sunlight||Yes||Best match to local thermal ecosystem|
|2||Wind||Yes||Can provide power at night|
|3||Water||Yes||Coupled with a dam, flow can be matched to usage|
|4||Sunlight||No||Non-polluting (in operation)|
|5||Wind||No||Can be unsightly en masse|
|6||Water||No||Limited opportunities, costly and with long durations to build|
|7||Petroleum||Yes||Polluting and expensive to run|
|8||Coal||No||Polluting, open-cut unsightly and underground hazardous to health|
|9||Nuclear||No||Dangerous pollutants produced, especially so with a plant meltdown|
Basically, local sources that are not in a latent form will have the least impact upon the earth's atmospheric temperatures.