Wednesday, September 05, 2007

Energy-generation: Conclusions.

Introduction

Today I'm concluding my six-part energy generation series. (Links: 1, 2, 3, 4, 5) I'll start with an overview of the structure for the final evaluation, then summarize my results thus far. Then will come the evaluation, plus a quick consideration of the recently-proposed Ontario government plan for energy development.

I had three categories of costs I was considering. First, input costs, which included such things as fuel, risk, and construction costs. Second, operating costs, including particularly repair and maintenance. Third, output costs, including particularly emissions. In terms of benefits, I had two categories, electricity (obviously) and indirect benefits.

Overview

All fossil fuel technologies have essentially the same constructions costs and the same risk. Extracting the fuels is done is basically the same way, and they are used in basically the same way. Fuel costs, however, vary. Coal is cheapest, and natural gas most expensive. This is because natural gas is harder to transport, and must be processed before it can be used. (Which processing, incidentally, produces waste that can be potentially environmentally-damaging.) They also all have basically the same operating costs. In particular, they all consume some elctricity, in order to return the water back to the boiler; and the water in the boiler must be regularly replenished, due to steam leaks. Their output costs are not identical, although all do produce high levels of emissions. Coal is by far the worst as, in addition to greenhouse gases, it releases toxic gases and radioactive material. Clean coal can, theoretically, solve these worries, but it hasn't yet been put into practice. In terms of benefits, all fossil fuels are low-efficiency, losing energy in the form of heat to the environment. Natural gas is the most efficient, however.

Hydro has no fuel costs at all. Dams can be low-cost, if they are placed to serve other, revenue-generating functions. There's no obvious risk associated with dam-building, except the risks that are always attendant on large-scale construction. Certainly, there's nothing like the extra risk that comes along with mining. Operating costs can be quite low, because dams last quite a while and don't require a lot of on-site supervision. There are strict limits on how many sites can be used to generate hydro power, though. They can also have serious effects on aquatic ecosystems. There's also a greenhouse gas output, at least potentially, if plant matter decays in the reservoirs. Output of power is hard to estimate, as it's highly contingent on the size of the dam. In principle, though, there's a fair bit of hydroelectric power that could be generated beyond what we already have.

Nuclear reactors require a significant amount of money and time for construction. However, fuel costs are far beyond fossil fuels, but my understanding is that far less fuel is required for a nuclear reactor than a fossil fuel plant producing comparable levels of power. The risk of obtaining the uranium is comparable to other mining endeavours; although, the mining process will release radiation into the surrounding environment. By law, mining companies must contain this radiation. Maintenance and repair costs of nuclear reactors are lower than fossil fuel plants, but security costs are higher. Fhe fission reaction also produces nuclear waste that has to be disposed of. It can, however, be reprocessed for re-use in reactors and as weapons material. There's also less radioactive waste produced from a nuclear plant than a coal plant, and far less than is produced by industry. Radiation from a nuclear plant, in itself, has never been shown to have any significant health effect. Nuclear plants are also emissions-free, if you don't count water vapour.

Wind has only capital costs as far as input costs. As with hydro, there's a limit to the number of good sites available. However, given that wind is just starting to make itself a viable power source, there's many sites to still exploit. Operating costs are minimal, unless the turbines are operating in areas that exceed their operating tolerances, thus requiring additional technologies to keep them running (e.g., heaters and low-temperature lubricants for turbines operating in low-temp conditions). Wind outputs no emissions. Turbines may be considered unsightly, however. Noise pollution is a bit of a non-issue, given that it is quieter and less frequent than, say, a nearby highway. However, the efficiency of a wind turbine isn't much better than fossil fuels, due to the reduction in wind energy created by the wind passing through the turbine (and thus slowing down). Wind turbines will also output variable levels of power, due to variations in wind speed.

Biogas is, basically, a substitute for natural gas created by the bacterial breakdown of plant material and other organic matter. All the products of this production process must be treated before being removed from the digester, but this is no different than treating natural gas. Feedstock supply is an issue, so it's not clear whether this is much better than fossil fuel or nuclear power, in terms of its reliance on something as fuel. However, what biogas is generated from is, in principle, renewable. Furthermore, although biogas produces greenhouse gases, they are comprised of the carbon that was originally absorbed by the feedstock material in the first place. So, technically, biogas is carbon-neutral. Replanting the feedstock will keep the cycle closed by reabsorbing the carbon dioxide to fuel new feedstock growth.

When it comes to solar, photovoltaic technology has no fuel, and its construction costs are going down. (As far as I can tell, the current higher prices are a supply and demand problem, nothing more.) There's no obvious risk associated with it. It requires some maintenance (no way yet of estimating the cost of this), as panels can become damaged, particularly in large banks, such as in photovoltaic plants in Europe and Australia. Solar thermal plants also use no fuel, and their constructions costs are going down. There's also no obvious associated risk. These do also require, though, water from the environment, as does any thermal power plant; and electricity is consumed in pumping the water back through the system. Output is hard to estimate. Thermal systems have the worst conversion efficiencies, which are comparable to coal. There are no emissions, though, which has to be considered a big plus. Like wind, though, solar energy is variable.

Geothermal uses no fuel. Extra construction costs are mostly related to the boring of holes -- the remainder of the system is no more costly than a thermal fossil fuel plant. Operating costs are no different than any thermal power plant. Output costs should be minimal as no fuel consumed, no waste produced, and water/steam can be recycled and reused. The risk is that underground heat sources might be able to be depleted temporarily. However, with experience and management, there doesn't seem to be any reason why this fuel source couldn't be continuous and stable.

Tidal barrages are basically hydroelectric dams which use the tide to fill higher pools of water, and then create a fast-flowing stream to generate electricity. Thus, input and operating costs are identical to hydro. Output is not quite identical because, unlike hydroelectric, barrages will not be able to continuously generate power. They can only operate with the tides. However, the tides are at least reliable and predictable. Tidal stream generators are basically wind turbines underwater. All the same comments as with wind apply; except, as noted above, tides can be predicted. So, although the power supply isn't constant, it is at least regular. Wave energy is in very early development, but it, too, could be an emissions-free, predictable, reliable source of power. All these sources are, in principle, inexhaustible. There's vastly more energy in the tides than we could use in the predictable future.

Fuel cells are really a small-scale power source. I'm more interested in large-scale power generation, but I want it noted that small-scale is probably an idea whose time has come. We can, in principle, install fuel cell, wind, and solar technologies on our homes (and, if we're lucky, hydroelectric as well) to generate a not-insignificant amount of electricity for our own use. Personally, I look forward to the day when these technologies are as much a part of new home construction as central air.

Nuclear fusion is still really in early development. It does hold out the hope of extremely large quantities of energy generated from relatively small amounts of fuel. It remains to be seen whether the technological barries can be overcome, though.

Comparison

Overall, several of these technologies use no fuel (solar, geothermal, wind, tidal, hydro). Biogas uses a renewable fuel. Nuclear uses a fuel that we haven't yet reached the point of exhausting. Fossil fuels use a fuel that is currently cheap, but is looking to drastically increase in price as extraction becomes more difficult and world reserves start to run dry.

In terms of risk, several are no-risk (except the usual risks associated with building big things): solar, wind, tidal, hydro, biogas. Fossil fuels and nuclear both require mining, which can be very dangerous. Nuclear mining has the special problem of controlling radiation from leaking from the mine. Geothermal has a small potential risk of increased seismic activity from drilling.

In terms of construction, some of these are very big-ticket items, and those costs aren't going down any time soon: hydro, tidal (barrage), nuclear. I don't have any idea how much biogas costs, capital-wise. Fossil fuels don't require a lot of construction expense in order to be used, nor do solar, wind and tidal (wave or stream generator).

Repair, maintenance and other operating costs are very difficult to evaluate. Some technologies can run with very little supervision: tidal, wind, hydro. Others need to be monitored and periodically repaired: solar, geothermal, nuclear, fossil fuel, biogas. But it's hard to see exactly what the costs are in this area. I suspect a general lack of transparency on the part of energy generating companies. It's possible the data is available out there, I suppose, but it's deucedly hard to find.

In terms of waste, hydro, solar, geothermal, wind, tidal, nuclear are free of troubling emissions. Biogas emits greenhouse gases, but is carbon-neutral, as long as feedstock is replanted. Fossil fuels, as we know, emit all kinds of crap. Nuclear produces waste which can be reprocessed. Moreover, the radiation levels have not been demonstrated to be associated with any health risk, and are less than both coal plants and industrial pollution generally. Hydro and wind installations can disturb existing ecosystems; given the structural similarities, it's probable that tidal will face the same problem.

It's hard to see what will produce more electricity. Certainly there's more tidal and wind and solar power than we will ever use, but we may not be able to tap all of it. This category looks like a draw, really. Depending on how big we want the installation to be, we could build anything to serve any amount of power. (This will get into whether there's enough resources to build the plants, but that's another issue completely.) This isn't necessarily a bad result, though, because it means that energy output doesn't affect the resolution of the issue. That is, whatever amount of energy we get from a given technology isn't what decides whether or not we use it. It's important to note, though, that some of the renewable technologies will not output reliable power, namely solar, wind, and tidal.

Due to lack of available information, it's impossible to calculate the indirect benefits of any of these technologies.

Evaluation

So, in conclusion, it seems that fossil fuel plants have had their day. Their fuel costs are going up, they're not efficient, and their fuel supplies are becoming ever more limited. Nuclear I don't think has had its day yet. The fears of radioactive waste seem unfounded, and we aren't yet at the point of using up potential fuel. However, nuclear will, eventually, have had its day as it, too, relies on a limited fuel supply. The advantage to nuclear over all the other technologies is that we know how to make it work, it's reliable, and we can, in principle, put nuclear plants just about anywhere (as compared to solar, wind, hydro, geothermal, and tidal, which are limited to locations that (a) don't destroy the surrounding environment and (b) are capable of producing reasonable amounts of electricity). So, short-term, we pretty much have to build nuclear to deal with our power needs. But, beyond that, there's no clear winner among the various technologies. Which suggests to me an obvious solution: let the market decide.

No, seriously. Let the market figure it out. Intervening to force a solution one way or the other when there's no clear reason to do so is central planning of the very worst sort. The better way to deal with our energy problems is for government to invest in nuclear (which we know works) while providing non-targetted subsidies for anyone who wants to try another technology out. That is, instead of funding one replacement for nukes in particular -- say, solar -- it is the role of government, representing our interests, to give everyone who wants the shot a chance to make their technology work. I envision these as investments, rather than loans, with the public retaining a share of the profits of successful companies, and losing their money if the company doesn't work. This would have two beneficial effects over a credit scheme: (1) failed start-ups don't have to deal with a debt burden on top of their failure and (2) government will be less willing to spend public money without a reasonable expectation of a return on the investment. Thus, we create a situation which encourages reasonable experimentation, fulfills our current and projected power needs, and will, eventually, give us a viable replacement for nuclear. Of course, if a clear winner does emerge from the market competition, then government should immediately target investment in that area in order to encourage its development as such a replacement.

With that in mind, i think it's worth taking a quick look at the Ontario plan for future power development. (See here.) The Liberal plan is to spend about $27 billion on nuclear, which I agree with, obviously. There's about $10 billion to spend on conservation, energy efficiency, and other ways to reduce demand. I cautiously endorse this, while noting that conservation is pretty much a pipe-dream. If we move seriously to paperless work, libraries, etc., keep expanding our use of electronic devices, and so on and so forth -- heck, if we introduce electric cars (which would, after all, be entirely emissions-free, and potentially very efficient) -- then conservation won't really happen on a wide-scale. Efficiency is a laudable goal, though, as would targetted subsidies for people who want to install small-scale green energy generation technologies on their own property (e.g., photovoltaic cells). The "other ways" aren't spelled out in the article, so I can't know if they include such subsidies.

There's $15 billion for new wind and hydroelectric projects, which I don't agree with. As said, I think this money should be distributed to any technology that wants to take a shot at proving itself, not just hydro and wind. Furthermore, building hydro requires, as is noted, $4 billion in new transmission infrastructure just to get the electricity from the dams (in the north of the province) to where it's needed. It's also worth noting that hydro power is, in principle, limited. There's not that many locations where a dam would produce a reasonable amount of power and not destroy the surrounding environment. There's also $3 billion for gas plants, which is a head-scratcher, unless the idea is to provide a stopgap power source until the nuclear plants are up and running. If that's the point, then it makes some sense, but it's not clear from the article.

Next Week

I'm currently plotting a series on open access to research. I need to do some preliminary work to figure out how to structure the series. But, the point I'm hoping to be able to endorse is neither the current system, with very controlled access, nor the pie-in-the-sky system of total open access. Instead, I'm hoping to be able to endorse a system of improved access, with minimal entrance barriers. But, we'll see if that works out for me or not....

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