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Posts Tagged ‘batteries

the ACCC, coal, renewables, arguments, and the future

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Well as I watch my readership reduce to almost zero in its usual ups and downs I wonder whether to write just for myself or to attract a readership, so I’ll just go ahead and write, but I was amused to listen to Senator Matt Canavan, our Minister for Resources and a member of the Nationals, responding to the ACCC’s recommendations for bringing energy prices down. At one point he remarked ‘who cares where we get our fuel from?’, and compared the different fuel varieties to different types of ice-cream in a sweet shop. Presumably he was referring to encouraging an energy mix, but for someone who presumably knows something about resources, since he holds that portfolio (though that’s hardly ever proof of expertise in government), it struck me as bizarre. Who cares where we get our fuel from or what type it is? The Chinese government cares, for one. It has worked hard in recent years to combat pollution in Beijing, largely  in response to adverse publicity. China’s capital, ranked as the fifth most polluted city in China in 2011, has since dropped out of the top twenty, largely due to the adoption of cleaner, greener energy and technology. Unfortunately, many other cities in China’s highly populated and industrialised north-western region still suffer from an environment which has reduced life expectancy there by some 5.5 years, according to a joint study by Chinese and American university teams in 2013. This sadly suggests that the Chinese government appears to be more concerned with its international image than with protecting its own citizens from hazardous emissions. On the bright side, Beijing’s improvement indicates what can be done to improve environments when governments and industry get their act together.

Just as oils aint oils, fuels aren’t just fuels. Remember kerosene? I remember huddling over a kerosene heater in the seventies, along with student housemates. But in other parts, kero isn’t a past-tense energy source. In many of the poorest countries, particularly in Africa, it’s used for lighting, even though it’s toxic, causes frequent burns and fires, and produces inferior light. It has proved difficult to wean consumers from kerosene in these countries, even though there are potentially cheaper options available. There’s an interesting article about the problems and possible solutions here.

But really, since energy generation (i.e. using x,y, or z as fuel) is the number one cause of air pollution and global warming emissions, it’s not like comparing caramel praline with black raspberry crunch. Coal is of course the worst in terms of emissions. As of 2016, some 44% of US electricity comes from coal, but it accounts for 80% of that country’s power plant carbon emissions. Australia has great reserves of coal, but it exports much of it to China and, more recently, South-East Asia. In fact Australia has experienced a recent boom in coal exports, earning a record $56.5 billion in 2017. Unsurprisingly many conservative pollies are clamouring for more coal mines and more local use of the resource as a solution to our seemingly ever-rising energy costs. Maybe we too can pull out of the Paris Agreement? Of course, our massive coal exports do tend to undermine that agreement, while the government can congratulate itself on keeping domestic use within more or less acceptable limits (see graph above). Currently, we’re the largest coal exporter and the third largest exporter of carbon pollution in the world, behind Saudi Arabia and Russia. But of course it’s not our fault that other countries want to pollute with our resources, is it? We just take the money and keep our country clean (as do Norway, Denmark and Indonesia).

So considering our dubious status in terms of global emissions (but, as many experts point out, it’s a little arrogant to expect developing and transitioning countries like China, our biggest coal customer, to rapidly abandon a fuel that the developed world has used for so long, thereby gaining ascendancy), it’s interesting to note that AGL, Australia’s largest owner of coal fired power stations and biggest emitter of carbon dioxide, is continuing its push away from coal in spite of government pressure. Of course the government itself is divided on this, with Turnbull and Frydenberg largely at odds with the Nationals on the question of transition, but looking into the future, it seems inevitable that demand for coal will decline – the only question is the rate of that decline, which of course depends on how quickly other nations move away from coal. All of those nations have signed the Paris Agreement. Already, coal ports such as Newcastle, and Australia’s mining regions, are looking to diversify, and energy experts are debating the pursuance of a coal tax to support the industry as it transitions.

But Canavan and the Nationals are having none of this. They point to the above-mentioned boom and a currently accelerating demand, though Canavan is realistic enough to admit that future forecasts are reliably unreliable. Much will depend on cost declines and advancing technology in renewables, as well as various political scenarios.

Naturally the renewable energy sector is looking critically at what one of its experts calls the ‘series of scattershot proposals’ by the ACCC on reducing our electricity costs. The ACCC’s recommendation that the small-scale renewable energy scheme (SRES), a subsidy which mainly applies to rooftop solar, should be wound down, is seen as unfair if not counter-productive by the sector. The SRES is already slated to be wound down by 2030, and its earlier abolition (by 2021, according to ACCC recommendations) would mainly affect low-income and rental householders. There’s currently a new boom in rooftop solar, with rising energy costs being the main cause. So penalising future adopters of rooftop solar seems an odd way to reduce the problems they’re adopting solar to avoid. As to the possibility of new gas- or coal-fired power plants, a dream of the Nationals and renegade ultra-conservative Tony Abbott, that’s unlikely, considering changing public attitudes and the reasonable likelihood of a change of federal government by next year. The good thing about the ACCC’s analysis is that the behaviour of retailers, and the phenomenon of price gouging, have finally been criticised, and the idea of states writing down the value of their networks has been floated. Consumers shouldn’t have to bear the burden of extra energy infrastructure and errors in predicting future energy demand.

There have been many interesting responses to the report, to say the least. Danny Price, a leading analyst of the national energy market over three decades, regards the report as overly political in that it shies away from criticising the lack of a much-needed bipartisan approach to energy policy. Confusion and ideological squabbling over carbon pricing – the disastrous scrapping by the Abbott government of a carefully formulated carbon tax being the low point – has been a disincentive to major investment, and banks here are refusing to finance new coal-fired power stations, which would only be built via massive government subsidies. Consequently we’ve seen an upsurge in interest in renewables from consumers and business, which also reflects worldwide growth, with major oil companies like BP joining the fray.

Of course the problem of reliable back-up power remains, and analyst Ian Verrender has criticised the ACCC report for omitting his best solution – gas. Gas turbines are more flexible than coal generators as well as producing fewer emissions. Australia is a major exporter of gas, but our companies have been providing little for domestic consumption, a situation which was only partly remedied by recent federal intervention. Yet the Nationals are more interested in coal than gas, in spite of its many problems, and its inefficiencies in providing precise back-up supply. Gas, hydro and batteries are far more efficient in this respect.

A recent study by the Australian Energy Market Operator (AEMO) has also backed renewables (though apparently the current federal government isn’t listening). It has released its Integrated Systems Plan, reported on here by Giles Parkinson:

Based on its “neutral” scenario, which comprises existing federal and state government policies, the lowest cost replacement [for retiring coal-fired suppliers] will be solar (28GW), wind (10.5GW) and storage (17GW and 90GWh). Just 500MW of flexible gas plant will be needed, and no new coal. It says this portfolio in total can produce 90TWh (net) of energy per annum, more than offsetting the energy lost from retiring coal fired generation.

AEMO has also highlighted the need for new transmission infrastructure, as transformative and disruptive energy developments continue around the country. The need for forward planning should be obvious and governments – especially the federal government – ignore this at their peril. A change of federal government may be the answer, but only if the incoming government has a thorough-going plan to integrate and manage this clear and obvious national move away from fossil fuels. Such plans are already being drawn up – we just need the will, and some bipartisan support, to implement them.

 

 

 

 

Written by stewart henderson

July 17, 2018 at 5:01 pm

Posted in ACCC, gas

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the continuing story of South Australia’s energy solutions

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In a very smart pre-election move, our state Premier Jay Weatherill has announced that there’s a trial under way to install Tesla batteries with solar panels on over 1,000 SA Housing Trust homes. The ultimate, rather ambitious aim, is to roll this out to 50,000 SA homes, thus creating a 250MW power plant, in essence. And not to be outdone, the opposition has engaged in a bit of commendable me-tooism, with a similar plan, actually announced last October. This in spite of the conservative Feds deriding SA labor’s ‘reckless experiments’ in renewables.

Initially the plan would be offered to public housing properties – which interests me, as a person who’s just left a solarised housing association property for one without solar. I’m in community housing, a subset of public housing. Such a ‘virtual’ power plant will, I think, make consumers more aware of energy resources and consumption. It’s a bit like owning your own bit of land instead of renting it. And it will also bring down electricity prices for those consumers.

This is a really important and exciting development, adding to and in many ways eclipsing other recently announced developments in SA, as written about previously. It will be, for a time at least, the world’s biggest virtual power plant, lending further stability to the grid. It’s also a welcome break for public housing tenants, among the most affected by rising power bills (though we’ll have to wait and see if prices do actually come down as a result of all this activity).

And the announcements and plans keep coming, with another big battery – our fourth – to be constructed in the mid-north, near Snowtown. The 21MW/26MWh battery will be built alongside a 44MW solar farm in the area (next to the big wind farm).

 

South Australia’s wind farms

Now, as someone not hugely well-versed in the renewable energy field and the energy market in general, I rely on various websites, journalists and pundits to keep me honest, and to help me make sense of weird websites such as this one, the apparent aim of which is to reveal all climate scientists as delusionary or fraudsters and all renewable energy as damaging or wasteful. Should they (these websites) be tackled or ignored? As a person concerned about the best use of energy, I think probably the latter. Anyway, one journalist always worth following is Giles Parkinson, who writes for Renew Economy, inter alia. In this article, Parkinson focuses on FCAS (frequency control and ancillary services), a set of network services overseen by AEMO, the Australian Energy Market Operator. According to Parkinson and other experts, the provision of these services has been a massive revenue source for an Australian ‘gas cartel’, which has been rorting the system at the expense of consumers, to the tune of many thousands of dollars. Enter the big Tesla battery , officially known as the Hornsdale Power Reserve (HPR), and the situation has changed drastically, to the benefit of all:

Rather than jumping up to prices of around $11,500 and $14,000/MW, the bidding of the Tesla big battery – and, in a major new development, the adjoining Hornsdale wind farm – helped (after an initial spike) to keep them at around $270/MW.

This saved several million dollars in FCAS charges (which are paid by other generators and big energy users) in a single day.

And that’s not the only impact. According to state government’s advisor, Frontier Economics, the average price of FCAS fell by around 75 per cent in December from the same month the previous year. Market players are delighted, and consumers should be too, because they will ultimately benefit. (Parkinson)

As experts are pointing out, the HPR is largely misconceived as an emergency stop-gap supplier for the whole state. It has other, more significant uses, which are proving invaluable. Its effect on FCAS, for example, and its ultra-ultra-quick responses to outages at major coal-fired generators outside of the state, and ‘its smoothing of wind output and trading in the wholesale market’. The key to its success, apparently, is its speed of effect – the ability to switch on or off in an instant.

Parkinson’s latest article is about another SA govt announcement – Australia’s first renewable-hydrogen electrolyser plant at Port Lincoln.

I’ve no idea what that means, but I’m about to find out – a little bit. I do know that once-hyped hydrogen hasn’t been receiving so much support lately as a fuel – though I don’t even understand how it works as a fuel. Anyway, this plant will be ten times bigger than one planned for the ACT as part of its push to have its electricity provided entirely by renewables. It’s called ‘green hydrogen’, and the set-up will include a 10MW hydrogen-fired gas turbine (the world’s largest) driven by local solar and wind power, and a 5MW hydrogen fuel cell. Parkinson doesn’t describe the underlying technology, so I’ll have a go.

It’s all about electrolysis, the production of hydrogen from H2O by the introduction of an electric current. Much of what follows comes from a 2015 puff piece of sorts from the German company Siemens. It argues, like many, that there’s no universal solution for electrical storage, and, like maybe not so many, that large-scale storage can only be addressed by pumped hydro, compressed air (CAES) and chemical storage media such as hydrogen and methane. Then it proceeds to pour cold water on hydro – ‘the potential to extend its current capacity is very limited’ – and on CAES ‘ – ‘has limitations on operational flexibility and capacity. I know nothing about CAES, but they’re probably right about hydro. Here’s their illustration of the process they have in mind, from generation to application.

Clearly the author of this document is being highly optimistic about the role of hydrogen in end-use applications. Don’t see too many hydrogen cars in the offing, though the Port Lincoln facility, it’s hoped, will produce hydrogen ‘that can be used to power fuel cell vehicles, make ammonia, generate electricity in a turbine or fuel cell, supply industry, or to export around the world’.

So how does electrolysis (of water) actually work? The answer, of course, is this:

2 H2O(l) → 2 H2(g) + O2(g); E0 = +1.229 V

Need I say more? On the right of the equation, E0 = +1.229 V, which basically means it takes 1.23 volts to split water. As shown above, Siemens is using PEM (Proton Exchange Membrane, or Polymer Electrolyte Membrane) electrolysis, though alkaline water electrolysis is another effective method. Not sure which which method is being used here.

In any case, it seems to be an approved and robust technology, and it will add to the variety of ‘disruptive’ and innovative plans and processes that are creating more regionalised networks throughout the state. And it gives us all incentives to learn more about how energy can be produced, stored and utilised.

Written by stewart henderson

February 14, 2018 at 4:50 pm

the battery, Snowy Hydro and other stuff

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Let’s get back to batteries, clean energy and Australia. Here’s a bit of interesting news to smack our clean-energy-fearing Feds with – you know, Freudenberg, Morrison and co. The Tesla Big Battery successfully installed at the beginning of summer, and lampooned by the Feds, turns out to be doing a far better job than expected, and not just here in South Australia. Giles Parkinson reported on it in Renew Economy on December 19:

The Tesla big battery is having a big impact on Australia’s electricity market, far beyond the South Australia grid where it was expected to time shift a small amount of wind energy and provide network services and emergency back-up in case of a major problem.

Last Thursday, one of the biggest coal units in Australia, Loy Yang A 3, tripped without warning at 1.59am, with the sudden loss of 560MW and causing a slump in frequency on the network.

What happened next has stunned electricity industry insiders and given food for thought over the near to medium term future of the grid, such was the rapid response of the Tesla big battery to an event that happened nearly 1,000km away.

The Loy Yang brown coal fired power station is in south eastern Victoria, so why did South Australia’s pride and joy respond to a problem in our dirty-coal neighbouring state? It surely wouldn’t have been contracted to, or would it? Parkinson also speculates about this. Apparently, when a power station trips, there’s always another unit contracted to provide back-up, officially called FCAS (frequency control and ancillary services). In Loy Yang’s case it’s a coal generator in Gladstone, Queensland. This generator did respond to the problem, within seconds, but the Tesla BB beat it to the punch, responding within milliseconds. That’s an important point; the Tesla BB didn’t avert a blackout, it simply proved its worth, without being asked. And it has been doing so regularly since early December. It seems the Tesla BB has cornered the market for fast frequency control. Don’t hold your breath for the Feds to acknowledge this, but they will have taken note, unless they’re completely stupid. They’ll be finding some way to play it (or downplay it) politically.

As Parkinson notes in another article, the energy industry has been slow to respond, in terms of regulation and accommodation, to the deployment of battery systems and their rapid charge-discharge features. Currently, providing FCAS is financially rewarded, which may have to do with costs involved but the cost/reward relationship appears to be out of kilter. In any case, battery response is much more cost-effective and threatens the antiquated reward system. The AEMC is planning to review frequency control frameworks, but it’ll no doubt be a slow process.

This is an incredibly complex area, combining new, barely-understood (by me) technologies of generation and storage, and the transformation of long-standing energy economies, with a host of vested interests, subsidies and forward plans, but I intend to struggle towards enlightenment, as far as I can.

Neoen’s Hornsdale Wind Farm

Regardless of regulation and grid problems, renewable energy projects keep on popping up, or at least popping into my consciousness through my desultory reading (NY resolution: inform myself much more on what’s going on, here and elsewhere, in clean energy). For example, the Murra Warra wind farm’s first stage will have an output of 226MW,  which has already been sold to a consortium of Australian corporations including Telstra and ANZ. The farm is near Horsham in western Victoria, and will finally have a capacity of up to 429MW, making it one of the biggest in the Southern Hemisphere. And of course there are many other projects underway. Back in August, the Renewable Energy Index, a monthly account of the renewable energy sector, was launched. Its first publication, by Green Energy Markets, was a benchmark report for 2016-7, all very glossy and positive. The latest publication, the November index, shows that rooftop solar installations for that month broke the monthly record set in June 2012 when subsidies were twice to three times what they are today. The publication’s headline is that the 2020 RET will be exceeded and that there are ‘enough renewable energy projects now under development to deliver half of Australia’s electricity by 2030’. The Clean Energy Council, the peak body for Australian dean energy businesses, also produces an annual report, so it will be interesting to compare its 2017 version with the Renewable Energy Index.

Hydro is in fact the biggest clean energy provider, with 42.3% of the nation’s renewable energy according to the 2016 Clean Energy Australia Report. Wind, however, is the fastest growing provider. This brings me to a topic I’ve so far avoided: The $4 billion Snowy Hydro 2 scheme.

Here’s what I’m garnering from various experts. It’s a storage scheme and that’s all to the good. As a major project it will have a long lead time, and that’s not so good, especially considering the fast growing and relatively unpredictable future for energy storage. As a storage system it will be a peak load provider, so can’t be compared to the Hazelwood dirty coal station, which is a 24/7 base load supplier. There’s a lot of misinformation from the Feds about the benefits, eg to South Australia, which won’t benefit and doesn’t need it, it’s sorting its own problems very nicely thanks. There’s a question about using water as an electricity supplier, due to water shortages, climate change and the real possibility of more droughts in the future. There are also environmental considerations – the development is located in Kosciuszko National Park. There’s some doubt too about the 2000MW figure being touted by the Feds, an increase of 50% to the existing scheme. However, many of these experts, mostly academics, favour the scheme as a boost to renewable energy investment which should be applied along with the other renewables to transform the market. In saying this, most experts agree that there’s been a singular lack of leadership and common-sense consensus on dealing with this process of transformation. It has been left mostly to the states and private enterprise to provide the initiative.

 

With each post I’ll add something on the projected Trump downfall.

Just watched a CNN special report: The Trump Russia Investigation. It suggests to me that the notorious Trump Tower meeting, while nothing much in itself, is but a small piece of the growing case against Trump. It filled me in muchly on the much-discussed ‘dossier’ released just before Trump’s inauguration, the commandeering of Facebook by Russian operatives for a disinformation campaign, stirring up issues on immigration, gays, guns, etc, and much more. I still maintain that he won’t be in office by year’s end.

 

 

Written by stewart henderson

January 6, 2018 at 7:20 pm

an assortment of new technology palaver

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I like the inset pic – very useful for the Chinese

Western Australia lithium mining boom

I’m hearing, better late than never, that lithium carbonate from Western Australia is in big demand. The state already provides most of the world’s lithium for all those batteries used to run smart devices, electric vehicles, and large-scale storage batteries such as South Australia’s Tesla-Neoen thingy at Jamestown (now 80% complete, apparently). Emissions legislation around the world will only add to the demand, with the French and British governments planning to ban the sale of petrol and diesel vehicles by 2040, following similar plans by India and Norway, and the major investments in EVs in China. Australia’s government, of course, is at the other end of the spectrum re EVs, but I’ve no doubt we’ll get there eventually (we’ll have to!). Tesla, Volvo, Nissan, Renault, Volkswagen and Mercedes are all pushing more EVs into the marketplace. So now’s the time, according to Money Boffins Inc, to buy shares in lithium and other battery minerals (I’ve never bought a share in my life). This lithium mining boom has been quite sudden and surprising to many pundits. In January of this year, only one WA mine was producing lithium, but by mid-2018 there will be eight, according to this article. The battery explosion, so to speak, is bringing increased demand for other minerals too, including cobalt, nickel, vanadium and graphite. Australia’s well-positioned to take advantage. Having said that, the amount of lithium we’re talking about is a tiny fraction of what WA exports in iron ore annually, but it’s already proving to be a big boost to the WA economy, and a big provider of jobs.

battery recycling

Of course all of this also poses a problem, as mentioned in my last post, and it’s a problem that the renewable energy sector should be at least ideologically driven to deal with: waste and recycling. Considering the increasing importance of battery technology in our world, and considering the many toxic components of modern batteries, such as nickel, lead acid, cadmium and mercury, it’s yet another disappointment that there’s no national recycling scheme for non-rechargeable batteries. Currently only lead acid batteries can be recycled, and the rest usually end up in landfill or are sent to be recycled overseas. So it’s been left to the industry to develop an Australian Battery Recycling Initiative (ABRI), which has an interesting website where you can learn about global recycling and many other things batterial – including, of course, how to recycle your batteries. Also, an organisation called Clean Up Australia has a useful battery recycling factsheet, which, for my own educational purposes I’m going to recycle here, at least partly. Battery types can be divided into primary, or single-use, and secondary, or rechargeable. The primary batteries generally use zinc and manganese in converting chemical to electrical energy. Rechargeable batteries use a variety of materials, including nickel cadmium, nickel metal hydride and of course lithium ion chemistry. Batteries in general are the most hazardous of waste materials, but there are also environmental impacts from battery production (mining mostly) and distribution (transport and packaging). As mentioned, Australian batteries are sent overseas for recycling – ABRI and other groups are trying to set up local recycling facilities. Currently a whopping 97% of these totally recyclable battery units end up in landfill, and – another depressing factoid – Australia’s e-waste is growing at 3 times the rate of general household waste. So the public is advised to use rechargeable batteries wherever possible, and to take their spent batteries to a proper recycling service (a list is given on the fact sheet). The ABRI website provides a more comprehensive list of drop-of services.

2015 registrations: Australia’s bar would be barely visible on this chart

EVs in Australia – a very long way to go

I recently gave a very brief overview of the depressing electric vehicle situation in Australia. Thinking of buying one? Good luck with that. However, almost all motorists are much richer than I am, so there’s hope for them. They’re Australia’s early adopters of course, so they need all the encouragement we can give them. Journalist Timna Jacks has written an article for the Sydney Morning Herald recently, trying to explain why electric vehicles have hit a dead end in Australia. High import duties, a luxury car tax and a lack of subsidies and infrastructure for electric vehicles aren’t exactly helping the situation. The world’s most popular electric car, the Nissan Leaf, is much more expensive here than in Europe or the US. And so on. So it’s hardly surprising that only 0.1% of all cars sold in Australia in 2015 were electric cars (compared with 23% and rising in EV heaven, aka Norway, 1.4% in France and 0.7% in the US). Of course Australia’s landscape’s more or less the opposite of compact, dense and highly urbanised Europe, and range anxiety might be a perennial excuse here. We have such a long way to go. I expect we’ll have to wait until shame at being the world’s laughing-stock is enough of a motivation.

Adelaide’s Tindo

I’ve been vaguely aware of Adelaide’s ‘green bus’ for some years but, mea culpa, haven’t informed myself in any depth up until now. The bus is called Tindo, which is a Kaurna aboriginal word meaning the sun. Apparently it’s the world’s first and only completely solar powered electric bus, which is quite amazing. The bus has no solar panels itself, but is charged from the solar panels at the Franklin Street bus station in the city centre. It’s been running for over four years now and I’m planning to take a trip on it in the very near future. I was going to say that it’ll be the first time I’ve been on a completely electric vehicle with no internal combustion engine but I was forgetting that I take tram trips almost every day. Silly me. Still, to take a trip on a bus with no noisy engine and no exhaust fumes will be a bit of a thrill for me. Presumably there will be no gear system either, and of course it’ll have regenerative braking – I’m still getting my head around this stuff – so the ride will be much less jerky than usual.

So here are some of the ‘specs’ I’ve learned about Tindo. It has a range of over 200 kilometres (and presumably this is assisted by the fact that its route is fixed and totally urban, so the regen braking system will be charging it up regularly). It uses 11 Swiss-made Zebra battery modules which are based on sodium nickel chloride, a type of molten salt technology. They have higher energy density, they’re lightweight and virtually maintenance free. According to the City of Adelaide website the solar PV system on the roof of the bus station is (or was – the website is annoyingly undated) ‘Adelaide’s largest grid-connected system, generating almost 70,000 kWh of electricity a year’. No connection to the ‘carbon-intensive South Australian electricity grid’ is another plus, though to be fair our grid is far less carbon intensive than Victoria’s which is almost all brown coal. South Australia’s grid runs on around half gas and half renewables, mostly wind. The regen braking, I must remind myself, means that when decelerating the bus uses no energy at all, and the motor electronically converts into an electrical generator, which generates electricity with the continued forward motion of the bus. There are many more specs and other bits of info on this Tindo factsheet.

battery technology and the cobalt problem

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The battery in my iPhone 6+ is described as a lithium polymer, or Li-ion polymer battery. I’m trying to find out if it contains cobalt. Why? Because cobalt is a problem.

According to this Techcrunch article, most of the world’s cobalt is currently sourced from Africa, especially the Congo, one of the world’s poorest countries. Child labour is regularly used in the mines there, under pain of beatings and other forms of coercion. The battery industry uses about 42% of global cobalt production, and the rest is used in a range of essential military-industrial applications.

Incidentally, this article from teardown.com blog goes deep inside the iPhone 6+ battery, showing that it uses lithium cobalt oxide (LiCoO2) for the cathode.

I can think of three possible ways out of this problem. 1. Stop sourcing cobalt from the Congo, or anywhere else that has exploitative labour practices. 2. Reform those labour practices, to improve the lives of the workers and provide them with a fairer share of the tech revolution profits. 3. Find an alternative to cobalt for batteries and other applications.

I didn’t say there were easy solutions haha. Anyway, let’s examine them.

An online Fortune article from March this year, which by the way confirms that cobalt is indeed used in iPhone and iPad batteries, reported that Apple has responded to investigative articles by Washington Post and Sky News by no longer buying cobalt from companies that employ child labour. Of course, even if we take Apple at its word – and considering that the Congo provides 60% of the world’s cobalt, and other African sources may have similar problems, how else will Apple be able to source cobalt cheaply? – the problem of Congolese child labour remains. The Washington Post report focused on a Chinese company, Zhejiang Huayou Cobalt Company, which purchases a large percentage of Congolese cobalt. It seems highly unlikely that such a company will be as affected by public or media pressure as Apple. However, there are some positive signs. A report in the Financial Times from a year ago, entitled ‘China moves to quell child labour claims in Congo cobalt mines’, says that China has launched a ‘Responsible Cobalt Initiative’ to improve supply chain governance and transparency. Whether this means applying solution 1 or solution 2 to the problem is unclear, but presumably it’s solution 2, and it really is a serious initiative, put forward by the Chinese Chamber of Commerce for Metals, Minerals and Chemicals Importers and Exporters, backed by the OECD and involving a number of international tech companies. Of course we’ll have to wait for reports on how this initiative is faring, and on whether these companies are concerned to improve the lives of cobalt miners or simply to ban the under-age ones while still paying very little to the remainder. Continued scrutiny is obviously necessary.

Of course, solution 3 would be of most interest to tech-heads (though presumably the effect on the Congolese economy would be terrible). According to this marketing article, there isn’t too much cobalt available, and the demand for it is increasing sharply. One problem is that cobalt isn’t generally mined on its own as ‘primary cobalt’ but as a byproduct of copper or nickel, and both of these metals are experiencing a worldwide price plunge, with many mines suspending activities. Also the current supply chain for cobalt is being dominated by Chinese companies. This could have a stifling effect especially on the EV revolution. Governments in advanced countries around the world – though not in Australia – are mandating the adoption of electric vehicles and the phasing out of fossil-fuel-based road transport. The batteries for these vehicles all contain cobalt.

In the TechCrunch article mentioned above, journalist Sebastien Gandon examines the Tesla situation. The company has a target of 500,000 vehicles a year by 2018, with cobalt sourced exclusively from North America. On the face of it, this seems unrealistic. Canada and the US together produce about 4% of the world’s cobalt supply, and  acccording to Gandon the maths just doesn’t add up, to say the least. For a start, the mining companies Tesla is looking to rely on are not even operational as yet.

However, there are a few more promising signs. The Tesla model S has been using high energy density nickel-cobalt-aluminium-based (NCA) battery cells, which have a lower cobalt content than the nickel-manganese-cobalt (NMC) batteries of most other companies. There is also the possibility of adopting lithium-iron-phosphate (LFP) chemistry, or lithium-manganese-oxide (LMO), neither of which use cobalt, though their lower energy density is a problem. In any case, battery technology is going through a highly intensive phase at present, as I’ve already reported, and a move away from cobalt has become a distinct possibility. Nickel is currently being looked at, but results so far have been disappointing. There are certainly other options in the offing, and cobalt itself, which unlike oil is completely recyclable, could still be viable with greater focus. It isn’t so much that it is scarce, it’s more that, in the past, it hasn’t been a primary focus, but mining it as a primary source will require substantial upfront costs, and substantial time delays.

So, all in all, it’s a problematic future, at least in the short term, for vehicles and technologies using cobalt-based battery systems. We can only wait and see what comes out of it.

Written by stewart henderson

October 28, 2017 at 12:55 pm

capacitors, supercapacitors and electric vehicles

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from the video ‘what are supercapacitors’

Jacinta: New developments in battery and capacitor technology are enough to make any newbie’s head spin.

Canto: So what’s a supercapacitor? Apart from being a super capacitor?

Jacinta: I don’t know but I need to find out fast because supercapacitors are about to be eclipsed by a new technology developed in Great Britain which they estimate as being   ‘between 1,000 and 10,000-times more effective than current supercapacitors’.

Canto: Shite, they’ll have to think of a new name, or downgrade the others to ‘those devices formerly known as supercapacitors’. But then, I’ll believe this new tech when I see it.

Jacinta: Now now, let’s get on board, superdisruptive technology here we come. Current supercapacitors are called such because they can charge and discharge very quickly over large numbers of cycles, but their storage capacity is limited in comparison to batteries…

Canto: Apparently young Elon Musk predicted some time ago that supercapacitors would provide the next major breakthrough in EVs.

Jacinta: Clever he. But these ultra-high-energy density storage devices, these so-much-more-than-super-supercapacitors, could enable an EV to be charged to a 200 kilometre range in just a few seconds.

Canto: So can you give more detail on the technology?

Jacinta: The development is from a UK technology firm, Augmented Optics, and what I’m reading tells me that it’s all about ‘cross-linked gel electrolytes’ with ultra-high capacitance values which can combine with existing electrodes to create supercapacitors with greater energy storage than existing lithium-ion batteries. So if this technology works out, it will transform not only EVs but mobile devices, and really anything you care to mention, over a range of industries. Though everything I’ve read about this dates back to late last year, or reports on developments from then. Anyway, it’s all about the electrolyte material, which is some kind of highly conductive organic polymer.

Canto: Apparently the first supercapacitors were invented back in 1957. They store energy by means of static charge, and I’m not sure what that means…

Jacinta: We’ll have to do a post on static electricity.

Canto: In any case their energy density hasn’t been competitive with the latest batteries until now.

Jacinta: Yes it’s all been about energy density apparently. That’s one of the main reasons why the infernal combustion engine won out over the electric motor in the early days, and now the energy density race is being run between new-age supercapacitors and batteries.

Canto: So how are supercapacitors used today? I’ve heard that they’re useful in conjunction with regenerative braking, and I’ve also heard that there’s a bus that runs entirely on supercapacitors. How does that work?

Jacinta: Well back in early 2013 Mazda introduced a supercapacitor-based regen braking system in its Mazda 6. To quote more or less from this article by the Society of Automotive Engineers (SAE), kinetic energy from deceleration is converted to electricity by the variable-voltage alternator and transmitted to a supercapacitor, from which it flows through a dc-dc converter to 12-V electrical components.

Canto: Oh right, now I get it…

Jacinta: We’ll have to do posts on alternators, direct current and alternating current. As for your bus story, yes, capabuses, as they’re called, are being used in Shanghai. They use supercapacitors, or ultracapacitors as they’re sometimes called, for onboard power storage, and this usage is likely to spread with the continuous move away from fossil fuels and with developments in supercaps, as I’ve heard them called. Of course, this is a hybrid technology, but I think they’ll be going fully electric soon enough.

Canto: Or not soon enough for a lot of us.

Jacinta: Apparently, with China’s dictators imposing stringent emission standards, electric buses, operating on power lines (we call them trams) became more common. Of course electricity may be generated by coal-fired power stations, and that’s a problem, but this fascinating article looking at the famous Melbourne tram network (run mainly on dirty brown coal) shows that with high occupancy rates the greenhouse footprint per person is way lower than for car users and their passengers. But the capabuses don’t use power lines, though they apparently run on tracks and charge regularly at recharge stops along the way. The technology is being adopted elsewhere too of course.

Canto: So let me return again to basics – what’s the difference between a capacitor and and a super-ultra-whatever-capacitor?

Jacinta: I think the difference is just in the capacitance. I’m inferring that because I’m hearing, on these videos, capacitors being talked about in terms of micro-farads (a farad, remember, being a unit of capacitance), whereas supercapacitors have ‘super capacitance’, i.e more energy storage capability. But I’ve just discovered a neat video which really helps in understanding all this, so I’m going to do a breakdown of it. First, it shows a range of supercapacitors, which look very much like batteries, the largest of which has a capacitance, as shown on the label, of 3000 farads. So, more super than your average capacitor. It also says 2.7 V DC, which I’m sure is also highly relevant. We’re first told that they’re often used in the energy recovery system of vehicles, and that they have a lower energy density (10 to 100 times less than the best Li-ion batteries), but they can deliver 10 to 100 times more power than a Li-ion battery.

Canto: You’ll be explaining that?

Jacinta: Yes, later. Another big difference is in charge-recharge cycles. A good rechargeable battery may manage a thousand charge and recharge cycles, while a supercap can be good for a million. And the narrator even gives a reason, which excites me – it’s because they function by the movement of ions rather than by chemical reactions as batteries do. I’ve seen that in the videos on capacitors, described in our earlier post. A capacitor has to be hooked up to a battery – a power source. So then he uses an analogy to show the difference between power and energy, and I’m hoping it’ll provide me with a long-lasting lightbulb moment. His analogy is a bucket with a hole. The amount of water the bucket can hold – the size of the bucket if you like – equates to the bucket’s energy capacity. The size of the hole determines the amount of power it can release. So with this in mind, a supercar is like a small bucket with a big hole, while a battery is more like a big bucket with a small hole.

Canto: So the key to a supercap is that it can provide a lot of power quickly, by discharging, then it has to be recharged. That might explain their use in those capabuses – I think.

Jacinta: Yes, for regenerative braking, for cordless power tools and for flash cameras, and also for brief peak power supplies. Now I’ve jumped to another video, which inter alia shows how a supercapacitor coin cell is made – I’m quite excited about all this new info I’m assimilating. A parallel plate capacitor is separated by a non-conducting dielectric, and its capacitance is directly proportional to the surface area of the plates and inversely proportional to the distance between them. Its longer life is largely due to the fact that no chemical reaction occurs between the two plates. Supercapacitors have an electrolyte between the plates rather than a dielectric…

Canto: What’s the difference?

Jacinta: A dielectric is an insulating material that causes polarisation in an electric field, but let’s not go into that now. Back to supercapacitors and the first video. It describes one containing two identical carbon-based high surface area electrodes with a paper-based separator between. They’re connected to aluminium current collectors on each side. Between the electrodes, positive and negative ions float in an electrolyte solution. That’s when the cell isn’t charged. In a fully charged cell, the ions attach to the positively and negatively charged electrodes (or terminals) according to the law of attraction. So, our video takes us through the steps of the charge-storage process. First we connect our positive and negative terminals to an energy source. At the negative electrode an electrical field is generated and the electrode becomes negatively charged, attracting positive ions and repelling negative ones. Simultaneously, the opposite is happening at the positive electrode. In each case the ‘counter-ions’ are said to adsorb to the surface of the electrode…

Canto: Adsorption is the adherence of ions – or atoms or molecules – to a surface.

Jacinta: So now there’s a strong electrical field which holds together the electrons from the electrode and the positive ions from the electrolyte. That’s basically where the potential energy is being stored. So now we come to the discharge part, where we remove electrons through the external surface, at the electrode-electrolyte interface we would have an excess of positive ions, therefore a positive ion is repelled in order to return the interface to a state of charge neutrality – that is, the negative charge and the positive charge are balanced. So to summarise from the video, supercapacitors aren’t a substitute for batteries. They’re suited to different applications, applications requiring high power, with moderate to low energy requirements (in cranes and lifts, for example). They can also be used as voltage support for high-energy devices, such as fuel cells and batteries.

Canto: What’s a fuel cell? Will we do a post on that?

Jacinta: Probably. The video mentions that Honda has used a bank of ultra capacitors in their FCX fuel-cell vehicle to protect the fuel cell (whatever that is) from rapid voltage fluctuations. The reliability of supercapacitors makes them particularly useful in applications that are described as maintenance-free, such as space travel and wind turbines. Mazda also uses them to capture waste energy in their i-Eloop energy recovery system as used on the Mazda 6 and the Mazda 3, which sounds like something worth investigating.

References (videos can be accessed from the links above)

http://www.hybridcars.com/supercapacitor-breakthrough-allows-electric-vehicle-charging-in-seconds/

https://en.wikipedia.org/wiki/Supercapacitor

http://www.power-technology.com/features/featureelectric-vehicles-putting-the-super-in-supercapacitor-5714209/

http://articles.sae.org/11845/

https://www.ptua.org.au/myths/tram-emissions/

http://www.europlat.org/capabus-the-finest-advancement-for-electric-buses.htm

Written by stewart henderson

September 5, 2017 at 10:08 am

what are capacitors?

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the shapes and sizes of capacitors – a screenshot taken from the youtube vid – What are Capacitors? – Electronics Basics 11

Jacinta: We’re embarking on the clearly impossible task of learning about every aspect of clean (and sometimes dirty because nothing’s 100% clean or efficient) technology – batteries, photovoltaics, turbines, kilo/megawatt-hours, glass electrolytes, powerwalls, inverters, regen, generators, airfoils, planetary gear sets, step-up transformers, nacelles AND capacitors.

Canto; Enough to last us a lifetime at our slow pace. So what, in the name of green fundamentalism, is a capacitor?

Jacinta: Well I’ve checked this out with Madam Youtube…

Canto: Professor Google’s co-dependent…

Jacinta: And in one sense it’s simple, or at least it sounds simple. Capacitors store electric charge, and the capacitance of a capacitor relates to how much charge it can hold.

Canto: So how does it do that, and what’s the purpose of storing electric charge?

Jacinta: Okay now you’re complicating matters, but basic to all capacitors are two separated pieces of conducting material, usually metal. Connected to a battery, they store charge…

Canto: Which is a kind of potential energy, right?

Jacinta: Umm, I think so. So take your battery with its positive and negative terminals. Attach one of the bits of conducting material (metal) to the positive terminal and you’ll get a flow of negatively-charged electrons to that terminal, because of ye olde law of attraction. This somehow means that electrons are repelled from the negative terminal  (which we’ve hooked up to the other bit of metal in the capacitor). So because the first strip of metal has lost electrons it has become positively charged, and the other bit of metal, having gained electrons, has an equal and opposite charge. So each piece of metal has the same magnitude of charge, measured in coulombs. This is regardless of the size and shape of the different metal bits.

Canto: But this process reaches a limit, though, yes? A kind of saturation point…

Jacinta: Well there comes a point where, yes, the accumulated charge just sits there. This is because there comes a kind of point of equilibrium between the positive battery terminal and the now positively charged strip of metal. The electrons are now caught between the attractive positive terminal and the positive strip.

Canto: Torn between two lovers, I know that foolish feeling.

Jacinta: So now if you remove the battery, so breaking the circuit, that accumulated charge will continue to sit there, because there’s nowhere to go.

Canto: And of course that accumulated or stored charge, or capacitance, is different for different capacitors.

Jacinta: And here’s where it gets really complicated, like you know, maths and formulae and equations. C = Q/V, capacitance equals the charge stored by the capacitor over the voltage across the capacitor. That charge (Q), in coulombs, is measured on one side of the capacitor, because the charges actually cancel each other out if you measure both sides, making a net charge of zero. So far, so uncomplicated, but try and get the following. When a capacitor stores charge it will create a voltage, which is essentially a difference in electric potential between the two metal strips. Now apparently (and you’ll have to take my word for this) electric potential is high near positive charges and low near negative charges. So if you bring these two differently charged strips into close proximity, that’s when you get a difference in electric potential – a voltage. If you allow a battery to fully charge up a capacitor, then the voltage across it (between the two strips) will be the same as the voltage in the battery. The capacitance, Q/V, coulombs per volt, is measured in farads, after Micky Faraday, the 19th century electrical wizz. I’m quoting this more or less verbatim from the Khan Academy video on capacitors, and I’m almost finished, but here comes the toughest bit, maths! Say you have a capacitor with a capacitance of 3 farads, and it’s connected to a nine volt battery, the charge stored will be 27 coulombs (3 = 27/9). 3 farads equals 27 coulombs of charge divided by nine volts, or 27 coulombs of charge is 3 farads times 9 volts. Or, if a 2 farad capacitor stores a charge of 6 coulombs, then the voltage across the capacitor will be 3 volts.

Canto: Actually, that’s not so difficult to follow, the maths is the easiest part for me… it’s more the concepts that get me, the very fact that matter has these electrical properties…

Jacinta: Okay here’s the last point made, more or less verbatim, on the Khan Academy video, something worth pondering:

You might think that as more charge gets stored on a capacitor, the capacitance must go up, but the value of the capacitance stays the same because as the charge increases, the voltage across that capacitor increases, which causes the ratio to stay the same. The only way to change the capacitance of a capacitor is to alter the physical characteristics of that capacitor (like making the pieces of metal bigger, or changing the distance between them).

Canto: Okay so to give an example, a capacitor might be connected to an 8 volt battery, but its capacitance is, say, 3 farads. It will be fully charged at 24 coulombs over 8 volts. The charge increases with the voltage, which has a maximum of 8. The ratio remains the same. Yet somehow I still don’t get it. So I’m going to have a look at another video to see if it helps. It uses the example of two metal plates. They start out as electrically neutral. You can’t force extra negativity, in the form of electrons, into one of these plates, because like charges repel, and they’ll be forced out again. But, according to the video, if you place another plate near the first, ‘as electrons accumulate in the first metal plate, they will repel the electrons in the second metal plate’, to which I want to respond, ‘but electrons aren’t accumulating, they’re being repelled’. But let’s just go with the electron flow. So the second metal plate becomes depleted of electrons and is positively charged. This means that it will attract the negatively charged first metal plate. According to the video, this makes it possible for the first plate to have more negative than positive particles, which I think has something to do with the fact that the electrons can’t jump from the first plate to the second, to create an equilibrium.

Jacinta: They’re kind of attracted by absence. That’s what they must mean by electric potential. It’s very romantic, really. But what you’ve failed to notice, is that a force is being continually applied, to counteract the repulsion of electrons from the first plate. If the force no longer applies then, yes, you won’t get that net negative charge in the first plate, and the consequent equal and opposite charge in the second. My question, though, is how can the capacitance increase by bringing the plates closer together? I can see how it can be changed by the size of the conducting material – more electrons, more electric potential. I suppose reducing the distance will increase the repulsive force…

Canto: Yes, let’s assume so. Any, a capacitor, which stores far less charge than a similarly-dimensioned battery can be used, I think, to briefly maintain power to, say, a LED bulb when it is disconnected from the battery. The capacitor, connected to the bulb will discharge its energy ‘across’ the bulb until it achieves equilibrium, which happens quite quickly, and the bulb will fade out. If the capacitor is connected to a number of batteries to achieve a higher voltage, the fully charged capacitor will take longer to discharge, keeping the light on for longer. If the metal plates are larger, the capacitor will take longer to charge up, and longer to discharge across the LED bulb. Finally, our second video (from a series of physics videos made by Eugene Khutoryansky) shows that you can place a piece of ‘special material’ between the two plates. This material contains molecules that change their orientation according to the charges on the plates. They exert a force which attracts more electrons to the negative plate, and repel them from the positive plate, which has the same effect as increasing the area of the plates – more charge for the same applied voltage.

Jacinta: An increase in capacitance.

Canto: Yes, and as you’ve surmised, bringing the two plates closer together increases the capacitance by attracting more electrons to the negatively charged plate and repelling them from the positively charged one – again, more charge for the same voltage.

Jacinta: So you can increase capacitance with a combo of the three – increased size, closer proximity, and that ‘special material’. Now, one advantage of capacitors over batteries is that they can charge up and discharge very quickly. Another is that they can endure many charge-discharge cycles. However they’re much less energy dense than batteries, and can only store a fraction of the energy of a same-sized battery. So the two energy sources have different uses.

Canto: Mmmm, and we’ll devote the next post to the uses to which capacitors can be put in electronics, and EVs and such.

 

Written by stewart henderson

August 28, 2017 at 6:27 pm