The fundamental concept behind this paper is the principle that we will need to be smarter in the way we approach energy, whether it’s in the generation, storage or use of energy. In doing so I will try to bring together information from different disciplines, and tackle some of the fallacies that seem to crop up whenever discussions of this sort take place. There will be some opinions expressed, but I will try to back up those opinions with facts.
Some parts of this may seem basic and obvious, yet bear repeating, since some commentators don’t seem to understand the basics. Here’s the first obvious statement: it’s all about the energy. It is not primarily about cars, or taxes, or wind turbines, or politics, etcetera. These things are distractions, secondary to the primary questions of energy use: where does it come from, how is it stored, and where does it go?
Renewable energy sources currently have a long way to go before they can meet everyone’s energy needs today. This is not controversial, yet I have seen some commentators use this fact to dismiss the whole idea of renewable energy sources as fatally flawed and unworkable, which is fallacious. The bad news is that it simply won’t be possible to do a one shot “switch-over” to renewable energy sources. The good news is that we won’t need to do that. Fossil fuels are not going to vanish soon; a more likely scenario is that they will become more and more expensive first.
We already have a means of tying together disparate energy sources: electricity. It is possible to add renewable energy sources to current and future electrical grids, and this is already well under way. Electricity is the most “fungible” form of energy we have: we can turn just about any other energy source in to electricity, and it can be used just about everywhere we need energy. It is not a panacea, however, and we face significant technical challenges in getting it to where we need it.
electricity from near and far
Within a country or region, electrical grids tie producers and consumers of electricity together. In Ireland, for example, major hydro-electric generation occurs in the west of the country e.g. Ardnacrusha, which was once able to supply the electricity needs of the entire country. Power from that source is transmitted to the rest of the country via a national grid. To transmit electrical energy over long distances, it must be stepped up to a high voltage – the higher the better, because of the fundamental relationships between power, voltage, current and resistance, which I won’t go in to here. This adds expense and complexity, some energy is lost in the process, and it doesn’t fully solve the problem of energy losses in transmission. How much is lost is a tricky question to answer, depending on your source, but I have seen figures suggesting that over 40% of the electrical power in Ireland is lost in this fashion.
If remote power generation and transmission is so inefficient, what can we do about it? More local generation sounds like a good idea. Using the example of Dublin, which previously took power from the other side of Ireland, there is now a local power station at Poolbeg, on the coast just to the east of the city. It is possible to go even more local, which falls under the heading of distributed generation. This is a subject of intense research today, and has been for years. What business or householder would not like to cut significantly reduce their electricity bills?
It isn’t quite as simple as mounting a wind turbine or a solar cell on the roof, since those sources are intermittent and unreliable. One approach is Combined Heating and Power (CHP or Cogeneration), in which fuel is burned to provide both electricity and heat, whether on a district-wide basis or on a domestic scale.
the need for smarts
transport and the “last mile” problem
to be continued