Disgreenimation

Hi there:

What a great word to identify what is a constant problem. I find that when people start to think about "going green" or fair trade or other issues that they seem to get into a maze of considerations. I encourage people to not be "too pure" - there is a place where a product is good enough for what is available at a given time, and we can hope that the strengthening of a market for green products will lead to improvements over time.

-- Zanna Joyce in Winnipeg

I often have a similar discussion with people about payback times for PV's or solar hot water etc. It often goes along these lines.
"So, what's the payback time for this solar hot water system?" "About ten years. Five to pay back the difference in price." "Not really worth it then is it?" "Why not?" "Well, it takes too long to pay off." "Why, how long does that marble benchtop take to payback? Or the new car in the driveway?" "That's different" "Why is it different?" "Because it is! Because I need the car for work and stuff!" "What about the benchtop" "Well, you've gotta have a benchtop, and marble is one of the best" "OK, what about the normal hot water service?" "What do you mean?" "How long does it take to pay back?" "It only costs half as much." "But how long to pay back." "Well, it doesn't.., I mean, they just cost you to run.., I mean.., oh look you're just being stupid!" "No, I'm serious. The solar hot water ends up being heaps cheaper than the normal one." "Yeah, well maybe.., Nah, look, I'm not really interested. Let's talk about something else."

I'm sure I'm not the only one who has had this conversation.

Cheers
MOC

Rather than the really long response I initially had, let me make this short. An article ("Photovoltaic solar cells: An overview of state-of-the-art cell development and environmental issues" by R.W. Miles*, K.M. Hynes, I. Forbes in Progress in Crystal Growth and Characterization of Materials, 51 of 2005) had one statement that sums it up. The statement essentially compared the pollution of a KWh of PV electricity production to approximately identical to that of coal or oil. So, although I am very much in favor of small-scale experimentation and continued progress, outfitting the whole world with PV right now would pollute just as much (if not more) than providing the same power - over the lifetime of the PV cells - as the oil or coal. And it would require the investment in huge amounts of infrastructure - including additional expenditures of oil and coal - just to produce the facilities that could turn the world solar, along with all the attendant depletion of resources and pollution. I think PV is getting close. The advances of the last decade have been fantastic in the energy efficiency (and to some degree material problems) of solar cell manufacture. But, at the moment, outfitting the world in solar cells as an alternative to fossil fuels would create more damage (remember the infrastructure) than the fossil fuels themselves. It's not a good trade off. At the same time, installation of present technology - using infrastructure that has already been built - is little or no worse than fossil fuels (and, for the locality in which it's installed, is better in many ways) and, I like to hope, helps advance the technology further. So, I'm not arguing against some installation of PV, only against some world-wide effort to implement it as a global retrofit (and I took the original post to which I responded as a musing of 'photovoltaicing the world') - it's not yet the obvious and only solution to our problem. By the way, I'll also put in my two cents worth on some other power technologies. I agree with solar hot water, no matter the payback; the cost is low (both economic and environmental, at least for a basic solar hot water collector) and every joule collected is one not taken from the earth otherwise (most often wasted on heating a vented roof). Wind is taking off all over, and has some great benefits. Unfortunately, its costs have yet to be well measured. For example, one of the eastern US sites is killing several thousand bats each year. For a slow-producing species (one or two offspring per season per pair) this could be a decimation over the life of the turbines, and bats are estimated by some to be some of the primary large-scale forest fertilizers and insect controls. In other areas, the kill rate is much lower... why? And the birds (especially raptors) have a similar problem. Until we know the details and can site these things where the damage isn't building to a potentially devastating point in fifty or one hundred years, I can't unconditionally support any effort to outfit every rise and coastline with wind turbines (and it seems that there is no shortage of companies willing to take advantage of the tax breaks provided for doing exactly that). But I do believe in building some, because they are better than the oil/coal production they replace at least short term (although even this is rather complicated and they're not nearly as good as they tend to look on the surface because of the characteristics of our generation and electricity demand...); we need to have examples on which to do the experimentation, to work out the problems, and to discover 'how far' we can go in harnessing wind energy and at what environmental cost; and it is a step in the right direction, physically, emotionally, politically. Similar problems exist for hydro (we tend to be decreasing hydro use because of the high environmental cost - but it's taken decades for that cost to become evident and may be too late to reverse in some places). Tidal, wave, and almost any other source of power will have their impacts and, if the impact becomes severe enough, will create environmental crises of their own. Every joule of energy that is used by humanity is some amount - at least a joule and usually far more - not available to the rest of the earth for what the earth was doing with it, and the earth was using it all before we came along. There is no free lunch - we can only hope to find the lunches that we can afford. We have a right to be here, but how much of the earth's energy can we consume? What are our rights? What are the rights of others - people, animals, plants? What are our obligations to all the 'others'? How much can we live without (how much can be sacrificed to our existence) before we too become extinct? I don't have the answers, but, as we consume ever more of the earth, we've got to ask the questions before taking the actions; the 'excess capacity' in ecosystem functions and adaptation that used to cushion our bad decisions isn't as large any more.

Anyway, I whole-heartedly support experimentation and further research; I think some use of PVs - especially at the present production scale with existing facilities - is a bonus and good thing - it keeps things going, does little harm, may do some good, etc. I don't want to create additional problems for the world that become another crisis in x number of decades and believe major 'jumps' in technologies need to be investigated thoroughly before jumping on the bandwagon... or we end up worse off than we are. Hence my statements about conservation and reduction. Reducing consumption has no (or extremely few) potential bad side effects. Everything else is suspect and should be scrutinized carefully before jumping... (and, on the socio-economic side of things, always remember that the PV technology is, by and large, owned by the same major corporations that bring you big oil... who argued that leaded gas was fine, claim still in many cases that there is no global warming due to human activity, that peak oil is a worry for another century... they may not be the best source of unbiased environmental information...) OK... too far, too negative... sorry, but I do have strong feelings about trying to reduce our footprint and even stronger ones about jumping onto a technological 'quick fix'. I think we probably will have to reduce our consumption (what's the environmental footprint up to now... 9 earths per average American? 2 per average human?). Some of that reduction may come about - more as quality-of-life improvement than reduction, maybe - through technology. But much may not, and there are many technological 'dead ends' that look great at one analysis perspective but, when viewed in a more holistic view, have problems ('safe' nuclear power, for example, is perfectly achievable, in my mind, at least by the nuclear industry's definition of safe... but what do we do with the tons of radioactive infrastructure when the plant finally must be retired? Present problems are simply delayed by 'storing' the waste as irradiated materials within the plant and plant infrastructure - piping, reactor vessel, pumps, concrete, rebar, etc. - until retirement...). On the other hand, arguing, talking, discussing is the best way to get the information out - I usually learn something and hope we all do! I do believe that we're all here for the same purposes and it's usually the back-and-forth of ideas that results in the best possible solutions!

Thank you! Peace!
Pete

Pete,

I agree with some points you made, particularly concerning reduction and conservation as a priority and I disagree with others such as your assertion that PV's are worse than oil or coal and I remain a little skeptical about your comments concerning the level of bat kills associated with wind farms. However, I also agree that we need to fully examine the impacts on any of the technologies we use and that open discussion is essential to work through issues such as these. One point about energy consumption deserves special comment "...Every joule of energy that is used by humanity is some amount - at least a joule and usually far more - not available to the rest of the earth for what the earth was doing with it, and the earth was using it all before we came along...." There are two fundamental differences between non-renewable energy sources such as coal, oil, gas, uranium and renewable energy such as wind, solar electric, solar thermal, hydro, and, to a lesser extent, biofuels and it has to do with the way energy flows into, through and out of the Planet. In order to explain this we need some background on how energy works on the Planet. This will take a few paragraphs. There are two basic sources of energy on the earth, the heat energy stored in the core of the planet that is very slowly seeping to the surface (and not so slowly in the case of volcanoes) and the other is the sunlight shining on the planet. Sunlight is, by far, the dominant source of all the energy that drives the weather and life on the planet. Of all the sunlight that arrives, some is reflected back into space, some is stored in plant material and animals and the rest is absorbed by the land, oceans and atmosphere. This energy drives weather patterns, causing rain, storms, floods, droughts, even snow and ice. Eventually, however, all of this energy turns into heat. All of it! As things warm up they radiate heat (mostly infrared). The earth is no different and radiates energy back into space. The temperature keeps rising until the amount of energy radiating back into space is equal to amount of energy received by the sun. At this point the average temperature is stable (over a period of time). If things change the ability of the earth to radiate into space then the temperature will change until energy flow is balanced again. This is the problem with greenhouse gases. They block some of the radiated energy and reduce the energy flow into space. This means the earth warms up until the energy flows are balanced again resulting in higher temperatures and consequential weather changes. (but I digress) Now, as we saw earlier, some of the energy is stored in plant material (and animals) but it is quite small compared to the total amount of energy striking the Earth. Big changes to the amount of plant and animal material on the Earth cause very very small temporary swings in the temperature while these changes are happening, but, for all practical purposes, they don't directly impact the overall energy flows to and from the planet. However, they can have very big impacts indirectly by altering the composition of the atmosphere and thereby changing the energy flows or by changing the way energy is reflected back into space (by exposure of bare ground, for example). Over a long period, large (to us) quantities of plant matter were converted into fossil fuels and this stored energy become unavailable to the normal energy flows on the planet. This was insignificant to the processes on the planet but it represented a large (to us) energy source that could be extracted and used by us (although Uranium is from a different source, similar aguments apply). Now the amount of energy contained in these fossil fuels is in addition to the normal energy flow from the sun and, in theory, it does make a difference directly on the energy flows and the temperature. On a planetary scale, however, it is still quite small and the difference is relatively insignificant. There are three things that are very important about this non-renewable energy source; 1) It is finite and exhaustible - once it's gone, it's gone forever 2) This energy is separate from the normal energy flows of the Earth 3) We now know that the secondary effects on the atmosphere are very significant Points 1 and 2 are particularly relevent to this discussion as we shall see. When you sit outside on a sunny early spring day and feel the delightfully warm sunlight bathing your body you are absorbing the energy that would have normally reached the ground where you are casting a shadow. As you warm up you will lose heat to the surroundings and that heat will travel via various processes and eventually end up radiated out into space. But what would happen if you weren't there? In the place where your shadow used to be the sunlight would heat up the ground and from there the heat would travel through many and varied processes and eventually end up radiated into space. What about a Solar hot water heater? The solar heater absorbs the energy that would normally hit the roof (and be dissipated into the surroundings) and stores it as hot water in a tank. Some time later when you use the hot water the heat enter the drains and through a variety of processes eventually radiates into space. In fact a whole passive design home behaves n the same way. Solar PV panels turn some of the energy into electricity which then powers lights and appliances that provide services but all the energy (including the light, sound, motion, etc.) eventually ends up as heat that gets radiated into space. Wind Turbines, hydro schemes and wave generators get their solar energy indirectly from the weather driven by the sun's energy. Even biomass energy comes indirectly from the sun. The point is that the energy from renewable sources is intercepted from the normal energy flow, utilised for a specific purposed and then returned to the normal flow as heat. In much the same way that a water wheel utilises the water flowing in a stream but does not actually consume the water. In theory, given a large enough interception of energy, we could disrupt the normal processes on the planet or at least in a particular region. This is extemely unlikely in the forseeable future as the total amount of energy arriving on earth far exceeds any possible amount of energy we could use. In the water wheel example it would be like putting a single water wheel on the banks of the amazon or even a dozen. Yes, there would be some local disruption at the site of the water wheel but the overall impact would be negligable. This discussion about energy does not take into account other things about the technologies we use that could have secondary effects and cause large disruptions. These include toxic waste in the technology processes (eg in the PV industry), environmental and habitat destruction from large Hydro or wave schemes, land clearing for houses, factories energy farms etc. But these are more to do with how we manage the technology and environment rather than an inherent problem with renewable energy. This then gives us the three things that are very important about renewable energy sources 1) They are inexhaustable but finite - there is a limit but they are constantly replenished 2) The energy is part of the normal energy flows on the Earth 3) The secondary effects are very technology specific but controllable So after all of that, we see that there shouldn't be a concern with harnessing renewable energy sources from an energy point of view. However, we should continue to, as Peter indicated, be skeptical and analyse the technologies carefully. Whew!

Cheers
MOC