Metals in short supply ?
February 13, 2010
A program from BBC Radio 4 that looks at possible shortages in the metals supply chain.
This link will only be active until Feb 18th, sorry.
http://www.bbc.co.uk/iplayer/episode/b00qjx5q/Out_Of_This_World/
Its an OK program. It covers the basics well, the researcher obviously found the two main sides of the argument. He didn’t chase down their fundamental positions though.
He looks a new technology as a solution mainly in recycling of metals, skipped over substitution in a sentence, had some kook from Surrey Uni muddying the waters with talk about space mining phosphorous (of course you aren’t going to mine bulk commodities in space to throw down Earth’s gravity well, that’s stupid ! If you were that desperate you’d use them to farm in space and throw the products down the well. Idiot !)
The guy who seems to being interviewed in a pub is a co-author of the UK’s only public, government sponsored report that I’ve seen on this topic. The report is OK, though quite why someone would employ a consultancy that specialises in the environmental impacts of waste disposal to conduct a metals supply study is a mystery. Its a bit like employing an undertaker to speak about health issues.
The MaterialsUK group is carrying out a much fuller examination of all this including something that I advocated in my thesis on copper supply, a full materials flow analysis to find out how much of what is where in the UK’s economy. Once you know that, only then can you really start to tailor policy towards material consumption. David King was right that we must eventually get to a post-consumption economy, but there are a few steps that we must take to get there. Knowing how we consume is one of them.
A quick question; at what point did mining engineers suddenly become the people who find minerals ? As a resource geologist I must have missed that meeting 
Just a final word on the whole materials security discourse. This is being driven by two main movements; the anti-consumption environmental movement and the American economic/energy independence/security side of the tracks. Bit of an unholy alliance really It should be recognised that the majority of pressure coming from West of the Atlantic is from the industrial/military and for those who are really interested; the US’s stance towards material security is embodied in the book “Minerals, Critical Minerals and the US Economy” . The majority of public pressure coming from Europe is from the anti-consumption angle, but economic imperatives to support high value, high-tech manufacturing in Germany and the Franco-centric nuclear industry are also important factors behind the scenes.
The flip side of the argument comes from the economists (Humphries on the program) and the materials scientists.
My own opinion is that there is no generalisation to be made here about materials running out on a global scale. Each material has a specific set of consumption pathways that it may take, each has a set of potential physical substitutes, each has a potential set of new sources, each has an availability to recycling, each technology that uses each material has its own pathway.
There is however likely to be issues over local availability as geology, politics and economics conspire to restrict efficient supply, and that really is the point. If we want to fight over ‘stuff’ we can, all we need to do is keep increasing its consumption without increasing the efficiency of its supply or recycling, human nature and politics will do the rest for us. However, since we know that conflict (physical or economic) is pretty much inevitable without concrete action to change course, do we not have an ethical responsibility to try and alter course whether it be though scientific/technological innovation or policy-led initiatives ?
The miners will mine only what they can sell, nothing other than economics is required to control that, so putting on the table products or policies that adjust consumption projections has to be the way to go.
Got even more wood ?
February 3, 2010
So DECC has launched a consultation document package for its Renewable Heat Initiative (RHI)
Lots of good stuff in there, but the bit that I’d like to comment on is the incentivisation of wood chip/wood pellets for domestic heating.
Feel free to correct me if I’m wrong but to me this provision looks like a commitment to an effective long term taxation of the rural poor. Its a bit counter-intuitive at first sight, after all how could an incentive to use local renewable biomass result in higher bills ? Well, its all to do with having a limited land package available to provide that biomass.
There is a distinction in the consultation between biomass that originates from wood, that which comes from grown for energy crops and that which is the result of existing agricultural processes (such as straw), but what concerns me is the interaction between existing managed woodland and possible new energy crops such as mycanthus and willow. The problem is that the RHI incentives only relate to pellet or chip burning boilers effectively replacing fossil-fuel burning boilers and central heating. Standing hardwood doesn’t make economic sense for pelletisation or chipping, its wears the machinery and takes more time and energy to produce and harvest.
What the consultation leaves out (and I can’t find mentioned anywhere in the document package) is the economic impact on existing wood users and those who cannot replace boilers. In other words me !
My situation is as follows: I live in a little village in Cornwall that is a good 10km from the nearest gas main. Most houses in the village use coal or wood to supplement Economy-7 electric heating. In many ways its a typical granite-built miners village. No cellars, very little outside space, houses are well over 100 years old (so low ceilings) and built of thick solid stone walls. Speaking for myself only; I don’t have a boiler, just an immersion heater that I turn on if and when I need hot water. I don’t have central heating, just a single electric storage heater that is powered by Economy-7 over-night. I rent the cottage and have only a small amount of space outside. I am not unusual in this county.
What I do have is a nice big fireplace that I can settle down in front of in the evening. I burn wood in that grate and buy my wood from local suppliers or one of the many local shops who sell 5kg bags of split logs over the counter.
My concern is that if pelletised or chipped wood becomes a lucrative product, managed woodland in the area will shift towards those products and away from larger trunked species suitable for splitting and domestic use. It’ll take time, I don’t expect to see the price that I pay for wood to rocket overnight, but the house that I live in will be around for at least another 100 years so the issue is not gong to go away. Over the 20-50 year timescale, by shifting the forestry from bulk wood to processed chip you will see a price differential mount that penalises those living in houses that cannot be physically altered to accommodate pellet burning boilers. These houses are generally smaller, cheaper and occupied by those less able to cope with price rises. Effectively this is an incentive that will put the rural poor at a greater disadvantage than ever.
I like the idea of increasing biomass use as I previously stated in Got Wood ?, but this particular policy seems poorly devised.
Copper in Wind Power
September 24, 2009
Based upon the research that I detailed in my previous post we can say the following with a reasonable degree of certainty;
The UK will need to increase its raw copper imports by at least 10%, from 2007 levels, if it is to achieve its wind power objectives AND manufacture the components of that new industry on British soil.
The further offshore that wind farms are built, the more copper they use per MW of installed generating capacity (kind of obvious but you still need to crunch the numbers to show it).
The UK currently exports more copper scrap per year than would be required by the proposed new wind industry, based on figures from the British Geological Survey.
The copper cables that are being buried during wind farm construction are not planned to be recovered upon decommissioning. This policy constitutes a planned consumption of copper that is contradictory to the principles of sustainable development since it ‘offshores’ energy consumption and environmental impact associated with copper production in preference to reuse. However, it provides the UK with a readily available source of copper in the form of recoverable buried cables with a known location. This could be considered a hedge against security of copper supply in the long term.
I have found no evidence that this possible long-term hedge against copper supply risk is a conscious and explicit government-led policy, but given that we have another 3 billion people coming to tea before 2075 and that copper has no viable substitute for 100% of its applications, it sounds like it might be a sound policy from a security of supply standpoint. Completely unethical of course, harvesting resources from other nations to hoard for future use, pushing up prices by artificially constraining supply and forcing developing nations to utilise resources earlier in their development cycle than they would have otherwise. But pragmatically better to establish a new form of copper mine within UK territory before supply really gets constrained.
The question is what are the alternatives ?
The obvious answer that I came up with was recycling. The UK only recycles about 42% of its scrap copper (from the BGS again). Of that 37% comes from manufacturing (offcuts, the remains after pressings, and the like), the rest is recycling as you and I know it. The old copper heating pipes and wires from old motors that we have finished with only make up 5% of the UK’s total copper (re-)consumption, 19 times more comes from new mined resources and from the pristine factory scrap. That is massively wasteful on all sorts of levels.
I recently read a paper on a Markov Chain analysis of copper (Eckelman & Daigo, 2008) use that concluded that the average copper atom was used 1.9 times for technology in the 60 years between its extraction from geological reserve and its dissipation back into the environment. If we assume that copper should theoretically be used around 20 times before it is dissipated (using a conservative 5% reprocessing loss), we currently have a copper system in the UK that is roughly 10% efficient.
That has to offer massive opportunities to the copper recycling business, as well as opportunities to decrease the environmental impact of the copper cycle without compromising the ability of the UK to meets its wind power goals.
Supply Chains Blowin’ in the Wind
September 18, 2009
This will be a very UK-centric post, but there are things that you could take away to apply to other countries if you wanted to. Be aware though that the data that I present here is not peer-reviewed and it is only semi-quantitative. I’m not an industrial electrician and I have had no access to detailed designs of wind farms. I asked several wind farm developers but had no success. For these reasons I’m going to call this an order of magnitude, or pathfinder study to be used to identify areas for further research rather than providing definitive ‘answers’.
It has deficiencies. I know what those deficiencies are. Don’t moan at me.
I’ve rounded everything in this post to nice figures. The nasty ones stay with me unless someone makes a specific request, but please remember, this is order of magnitude stuff. I think that I’m in the right ball park, but those with the hard data don’t want to pitch in (to stretch the baseball analogy).
I have tried to come up with a figure on the total amount of copper needed to satisfy the current UK policies on wind power, and while I’m sure that my findings are not news in the wind farm development community they may be interesting to others.
The UK’s wind energy strategy is to install around 37GW of new wind powered generating capacity over the next 10 years to 2020, and about another 10GW in the following 10 years. But we’ll deal with the first 10 years only because the degree of technology learning will be quite substantial and there are several disruptive technologies at the pre-commercial stage right now, especially in the field of high temperature super-conductors.
If we assume that the average size of conventional wind turbines installed through the next 10 years is 5MW, we’re looking at 7,400 new turbines. Some will be bigger, some smaller, but 5MW seems like a good place to start since there are several prototypes that size already working in Europe.
25GW (5,000) will be installed offshore, 12GW (2,400) onshore. This is the rough estimate put forward in the UK’s Low Carbon Strategy, but obviously subject to commercial realities.
Yes, I know that those onshore are likely to be restricted in size due to the planning regime and that bigger turbines may be developed offshore, but this is an order of magnitude study remember. It doesn’t actually matter that much how many turbines there, minimum safe copper usage is broadly proportional to the power that it is being used to generate and conduct (though for commercial, safety and regulatory reasons the actual engineering may break that proportionality, but again no-one was willing to tell me by how much).
So first things first.
How much copper is there in a wind turbine ?
Quick answer, just under 2 tonnes per MW of nameplate generating capacity.
I’ve used 4 peer-reviewed papers to get this answer, which I realise is quite a low number of data points and I’d like to get more data on the copper consumption of large modern turbines, but there are only a few peer-reviewed papers on this and some of them don’t have the data in a form that is usable. The largest turbine that was included here was 2MW, which is an other issue.
That means that just in the tower and nacelle each and every one of our 5MW wind turbines will contain around 10 tonnes of copper.
Sounds a lot ? A typical 5MW nacelle (with rotor, generator, gearbox and transformer) will weigh 150+ tonnes in total, so its really not that much in context.
We have our first estimate – 74,000 tonnes of copper embodied in the turbines. Easy.
Of course technology is moving fast within the mechanical portion of turbine development, with gearbox-less models, generators with super-conducting coils, generators with dynamic numbers of coils, etc, etc. So we can reasonably expect that figure to drop somewhat, even over just 10 years.
However, a wind turbine siting on its own is no use to man nor beast. What it needs is a connection to the grid. Cabling is a less dynamic technology. In fact cables haven’t really changed much in the last 50 years, despite that massive electrification of the industrialised nations during that time. Hell, there are probably cables in my street that are almost that old ! Don’t get me wrong cable performance has increased, but not really in terms of the amount of copper used, more in the engineering surrounding the conductors in terms of resistance to damage or corrosion, or lightness. In this field aluminium conductors don’t really get a look in.
In my workings I used the ‘off-the-shelf’ wind farm cable of choice, the Nexans 33kV (submarine version) for connecting both onshore & offshore turbines. Since what I’m interested in is the mass of copper conductor not the engineering around the cable, the actual version is not very important and Nexans provided the most complete datasheet.
At this point I will say that my methodology breaks down in large onshore wind farms with complex cabling topologies. Since no-one will show me their designs or costings, I have had to assume a ‘least distance’ method. In other words I’ve optimised for cable length, not wind farm cost. What my results show is that this is a reasonable assumption for onshore wind farms of about 30 turbines or less. Above that the cost of system elements, such as the sub-station, and the installation costs appear to start to exert a significant influence and I believe that my model over-estimates the amount of cabling used. The line of best fit to my data is logarithmic, so I’m guessing that my over-estimation gets worse the larger the wind farm is.
However, the number of onshore wind farms that have 30 or more turbines is low in the UK. I found 3 in this study of 30. Outside Scotland this is likely to remain the case due to constraints on space, and wind farms of 5 to 10 turbines currently typical in England and Wales.
Total copper use (without grid connection, because that is site specific) for onshore wind farms in the UK is 5.6 t/MW according to my model, with its warning attached for over estimation. A ‘safe’ estimate would be about 4 t/MW.
The methodology is more robust for offshore wind farms because the industry-standard cable topology seems to be single runs connecting rows of turbines with the single runs being gathered at the sub-station for conditioning and voltage step-up before transmission via the inter-connector.
Once you get to the inter-connector you are looking at a very serious piece of kit and a critical point of failure. You could loose one cable connecting a whole row a turbines and retain two thirds of output in a typical topology of a 3 row 30 turbine farm. Loose the inter-connector and you loose all output. Each inter-connector is a custom design. Fortunately, enough design detail is usually publicly available to make a good guess at the copper content (you need the total number of cables, number of turbines and their rated power output, and the transmission voltage to make an order of magnitude calculation). I only worked with 3-phase AC, since I could only find enough detail on one planned wind farm with HVDC.
So, to cut a long story short, my back-of-the-envelope calculation shows that offshore wind farms use copper at a rate of 9.6 t/MW by the time you connect them to the grid, with roughly one third of all copper being used in these installations contained in the inter-connector.
Not surprisingly the intensity of copper use goes up with length of inter-connector. My rough estimate is an additional 80kg of copper per MW per km of inter-connector. My R-squared is 0.31 on this, so there is a decent correlation, but its not brilliant. Note; distance to shore is not the same as inter-connector length. There may be a loose correlation between the two, but to give a couple of examples; one particular installation in German waters plans a 115km long inter-connector with 40km of that onshore, while another in the UK is 12km from shore but has a 43km cable route to the best available grid connection point.
To summarise;
Large wind turbines require around 2 tonnes of copper per MW of nameplate generating capacity.
Onshore they require a roughly similar amount in cabling infrastructure before you attach them to the grid, but my model overestimates the amount in large wind farms and this skews the result by a significant but undetermined amount. I estimate that my model doubles the cabling requirement in large onshore wind farms only, but I don’t have the hard data to back that up. A ‘safe’ estimate for total copper is therefore 4 t/MW onshore.
Offshore wind farms require more than double the copper per MW of installed capacity of their onshore cousins, but that includes the connection to the grid.
We will use 10 t/MW offshore and 4 t/MW onshore.
So this gives up our next estimate.
25GW offshore equals 250,000 tonnes of copper offshore
12GW onshore equals 48,000 tonnes of copper onshore
For a total of about 300,000 tonnes of new copper required just by UK wind power up to 2020.
Put that into context, in 2007 the UK exported 373,795 tonnes of copper and copper scrap (according to the BGS European Mineral Statistics)
Import trends from the same statistics show that copper will, effectively, no longer be imported into the UK as a raw material by 2011.
So even spread over 10 years at 30,000 tpa, this is a significant shift in raw material requirements for a country with virtually no manufacturing capacity left.
I’ll leave it there and discuss the potential implications in another post.
Rare media interest (except from The Guardian)
September 4, 2009
Rare Earth Elements. REEs. There I said it. Used the energy buzz words of last week (apart from ‘Giant’ and ‘Shell’).
I could turn this post into a list of all the media voices that have suddenly discovered that there is some stuff that China does that we can’t do at the moment and its a threat to the world because we can’t do it but China can. But that’s been done very effectively already with varying degrees of shrillness.
What was apparent from the coverage that I saw outside the specialist channels was the lack of appreciation that geology influences trade, economics and politics at a fundamental level. As a UK-ite and involved in the commodities sector, it appears impossible to me to separate the history of nation and then empire from that of energy availability, resource exploitation and commodities trade. They just run together in a continuum. But apart from the normal oil & gas stories, commodities mostly get overlooked and things like REEs might as well be fairy dust as far as mainstream media is concerned.
The rare earth story didn’t make it to the red tops, after all its not like China invaded Tokyo or some stick-thin media casualty just got slightly less stick-thin. But it made all of the other major UK newspapers, except The Guardian. The Guardian who started their 10:10 campaign to get my fellow UK-ites to reduce their carbon footprints by 10% by 2010. The Guardian who have one of the most vociferous environmental media campaigners around as a regular columnist in George Monbiot. I suppose there is a simplistic reason for that. Mining to provide material vital to almost all the significant new energy infrastructure does not fit the world view that mining is bad in each and every case. I hope that’s not the case this time. Most of their content is pretty intelligent and as a new media outlet they are well ahead of the curve. Not even a blip in the business section, nothing. The world’s proposed new low carbon energy system is facing an existential threat (as some would seem to have it) and it doesn’t apparently rate an inch or two, even in calm defense against hysterical hyperbolae. I’m not accusing The Guardian of being a bad news organisation, or of missing a story (I’m sure that they saw the same news wires as every one else), what I’m saying is that they are lacking nuance on this story in particular and that in not publishing their take on the story have made more of a comment than had they made comment.
The world is a complex and contradictory place and sometimes a story comes along that contradicts you and everything that you are saying. But that’s what journalism is for isn’t it ? Exposing the contradictions for what they are. Democratising information to allow proliferation of thought.
The uni-vocal will struggle to cope with that proliferation and loose credibility as a result. What the rare earth story demonstrates, to me at least, is that labelling an entire industry as bad, or dirty or unethical (or good, green and ethical) is as reductive as calling an animal evil. Now that’s the sort of story that the red tops can get their teeth into !
