Category Archives: technology

the tides – a massive potential resource?

A floating tidal turbine, Orkney islands, as seen on Fully Charged

A recent episode of Fully Charged, the Brit video series on the sources and harnessing of clean energy, took us again to the very windy Orkney Isles at the top of Scotland to have a look at some experimental work being done on generating energy from tidal forces. When you think of it, it seems a no-brainer to harness the energy of the tides. They’re regular, predictable, unceasing, and in some places surely very powerful. Yet I’ve never heard of them being used on an industrial scale.

Of course, I’m still new to this business, so the learning curve continues steep. Tide mills have been used historically here and there, possibly even since Roman times, and tidal barrages have been operating since the sixties, the first and for a long time the largest being the La Rance plant, off the coast of Brittany, generating 240 MW. A slightly bigger one has recently been built in Korea (254 MW).

But tidal barrages – not what they’re testing in the Orkneys – come with serious environmental impact issues. They’re about building a barrage across a bay or estuary with a decent tidal flow. The barrage acts as a kind of adjustable dam, with sluice gates that open and close, and additional pumping when necessary. Turbines generate energy from pressure and height differentials, as in a hydro-electric dam. Research on the environmental impact of these constructions, which can often be major civil engineering projects, has revealed mixed results. Short-term impacts are often devastating, but over time one type of diversity has been replaced by another.

Anyway, what’s happening in the Orkneys is something entirely different. The islanders, the Scottish government and the EU are collaborating through an organisation called EMEC, the European Marine Energy Centre, to test tidal power in the region. They appear to be inviting innovators and technicians to test their projects there. A company called ScotRenewables, for example, has developed low-maintenance floating tidal turbines with retractable legs, one of which is currently being tested in the offshore waters. They’re designed to turn with the ebb and flood tides to maximise their power generation. It’s a 2 MW system, which of course could be duplicated many times over in the fashion of wind turbines, to generate hundreds if not thousands of megawatts. The beauty of the system is its reliability – as the tidal flow can be reliably predicted at least eighteen years into the future, according to the ScotRenewables CEO. This should provide a sense of stability and confidence to downstream suppliers. Also, floating turbines could easily be removed if they’re causing damage, or if they require maintenance. Clearly, the effect on the tidal system would be minimal compared to an estuarine barrage, though there are obvious dangers to marine life getting too close to turbines. The testing of these turbines is coming to an end and they’ve been highly successful so far, though they already have an improved turbine design in the wings, which can be maintained either in situ or in dock. The design can also be scaled down, or up, to suit various sites and conditions.

rotors are on retractable legs, to protect from storms, etc

Other quite different turbine types are being tested in the region, with a lot of government and public support, but I got the slight impression that commercial support for this kind of technology is somewhat lacking. In the Fully Charged video on this subject (to which I owe most of this info), Robert Llewelyn asked the EMEC marketing manager whether she thought tidal or wave energy had the greatest future potential (she opted for wave). My ears pricked up, as wave energy is another newie for me. Duh. Another post, I suppose.

As mentioned though in this video, a lot of the developments in this tidal technology have come from shipbuilding technology, from offshore oil and gas technology, and from maritime technology more generally, as well as modern wind turbine technology, further impressing on me that skills are transferable and that the cheap clean energy revolution won’t be the economic/employment disaster that the fossil fuel dinosaurs predict. It’s a great time for innovation, insight and foresight, and I can only hope that more government and business people in Australia, where I seem to be stuck, can get on board.

fixed underwater tidal turbine being tested off the Orkney Islands

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capacitors, supercapacitors and electric vehicles

(this is reblogged from the new ussr illustrated, first published September 5 2017)

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

on the explosion of battery research – part two, a bitsy presentation

(this is reblogged from the new ussr illustrated, first published August 1 2017)

This EV battery managed to run for 1200 kilometres on a single charge at an average of around 51 mph

Ok, in order to make myself fractionally knowledgable about this sort of stuff I find myself watching videos made by motor-mouthed super-geeks who regularly do blokes-and-sheds experiments with wires and circuits and volt-makers and resistors and things that go spark in the night, and I feel I’m taking a peek at an alternative universe that I’m not sure whether to wish I was born into, but I’ll try anyway to report on it all without sounding too swamped or stupefied by the detail.

However, before I go on, I must say that, since my interest in this stuff stems ultimately from my interest in developing cleaner as well as more efficient energy, and replacing fossil fuel as a principal energy source, I want to voice my suspicions about the Australian federal government’s attitude towards clean and renewable energy. This morning I heard Scott Morrison, our nation’s Treasurer, repeating the same deliberately misleading comments made recently by Josh Frydenberg (the nation’s energy minister, for Christ’s sake) about the Tesla battery, which is designed to provide back-up power as part of a six-point SA government plan which the feds are well aware of but are unwilling to say anything positive about – or anything at all. Morrison, Frydenberg and that other trail-blazing intellectual, Barnaby Joyce, our Deputy Prime Minister, have all been totally derisory of the planned battery, and their pointlessly negative comments have thrown the spotlight on something I’ve not sufficiently noticed before. This government, since the election of just over a year ago, has not had anything positive to say about clean energy. In fact it has never said anything at all on the subject, by deliberate policy I suspect. We know that our PM isn’t as stupid on clean energy as his ministers, but he’s obviously constrained by his conservative colleagues. It’s as if, like those mythical ostriches, they’re hoping the whole world of renewables will go away if they pay no attention to it.

Anyway, rather than be demoralised by these unfortunates, let’s explore the world of solutions.

As a tribute to those can-do, DIY geeky types I need to share a great video which proves you can run an electric vehicle on a single charge for well over 1000ks – theirs made it to 1200ks – 748 miles in that dear old US currency – averaging around 51 mph. It’s well worth a watch, though with all the interest there are no doubt other claimants to the record distance for a single charge. Anyway, you can’t help but admire these guys. Tesla, as the video shows, are still trying to make it to 1000ks, but that’s on a regular, commercial basis of course.

In this video, basically an interview with battery researcher and materials scientist Professor Peter Bruce at Oxford University, the subject was batteries as storage systems. These are the batteries you find in your smart phones and other devices, and in electric vehicles (EVs). They’ll also be important in the renewable energy future, for grid storage. You can pump electricity into these batteries and, through a chemical process that I’m still trying to get my head around, you can store it for later use. As Prof Bruce points out, the lithium-ion battery revolutionised the field by more or less doubling the energy density of batteries and making much recent portable electronics technology possible. This energy density feature is key – the Li-ion batteries can store more energy per unit mass and volume. Of course energy density isn’t the only variable they’re working on. Speed of charge, length of time (and/or amount of activity) between charging, number of discharge-recharge cycles per battery, safety and cost are all vitally important, but when we look at EVs and grid storage you’re looking at much larger scale batteries that can’t be simply upgraded or replaced every few months. So Bruce sees this as an advantage, in that recycling and re-using will be more of a feature of the new electrified age. Also, as very much a  scientist, Bruce is interested in how the rather sudden focus on battery storage reveals gaps in our knowledge which we didn’t really know we had – and this is how knowledge often progresses, when we find we have an urgent problem to solve and we need to look at the basics, the underlying mechanisms. For example, the key to Li-ion batteries is the lithium compound used, and whether you can get more lithium ions out of particular compounds, and/or get them to move more quickly between the electrodes to discharge and recharge the battery. This requires analysis and understanding at the fundamental, atomistic level. Also, current Li-ion batteries for portable devices generally use cobalt in the compound, which is too expensive for large-scale batteries. Iron, manganese and silicates are being looked at as cheaper alternatives. This is all new research – and he makes no mention of the work done by Goodenough, Braga et al.

In any case it’s fascinating how new problems lead to new solutions. The two most touted and developed forms of renewable energy – solar and wind – both have this major problem of intermittence. In the meantime, battery storage, for portable devices and EVs, has become a big thing, and now new developments are heating up the materials science field in an electrifying way, which will in turn hot up the EV and clean energy markets.

The video ended by neatly connecting with the geeky DIY video in showing how dumped, abandoned laptop batteries and other batteries had plenty of capacity left in them – more than 60% in many cases, which is more than useful for energy storage, so they were being harvested by PhD students for use in small-scale energy storage systems for developing countries. Great for LED lighting, which requires little power. The students were using an algorithm to get each battery in the system to discharge at different rates (since they all had different capacities or charge left in them) so they could get maximum capacity out of the system as a whole. I think I actually understood that!

Okay – something very exciting! The video mentioned above is the first I’ve seen of a British series called ‘Fully Charged’, all about batteries, EVs and renewable energy. I plan to watch the series for my education and for the thrill of it all. But imagine my surprise when I started watching this one, still part of the series, made here in Adelaide! I won’t go into the content of that video, which was about flow batteries which can store solar energy rather than transferring it to the grid. I need to bone up more on that technology before commenting, and it’s probably a bit pricey for the likes of me anyway. What was immediately interesting to me was how quickly he (Robert Llewellyn, the narrator/interviewer) cottoned on to our federal government’s extreme negativity regarding renewables. Glad to have that back-up! I note too, by the way, that Australia has no direct incentives to buy EVs, of which there are few in the country – again all due to our troglodyte government. It’s frankly embarrassing.

So, there’s so much happening with battery technology and its applications that I might need to take some time off to absorb all the videos and docos and blogs and podcasts and development plans and government directives and projects and whatnot that are coming out all the time from the usual and some quite unusual places, not to mention our own local South Australian activities and the naysayers buzzing around them. Then again I may be moved to charge forward and report on some half-digested new development or announcement tomorrow, who knows….

References

They’re all in the links above, and I highly recommend the British ‘Fully Charged’ videos produced by Robert Llewellyn and Johnny Smith, and the USA ‘jehugarcia’ videos, which, like the Brit ones but in a different way, are a lot of fun as well as educational.

 

on the explosion of battery research – part one, some basic electrical concepts, and something about solid state batteries…

(this is reblogged from the new ussr illustrated, first published July 29 2017)

just another type of battery technology not mentioned in this post

Okay I was going to write about gas prices in my next post but I’ve been side-tracked by the subject of batteries. Truth to tell, I’ve become mildly addicted to battery videos. So much seems to be happening in this field that it’s definitely affecting my neurotransmission.

Last post, I gave a brief overview of how lithium ion batteries work in general, and I made mention of the variety of materials used. What I’ve been learning over the past few days is that there’s an explosion of research into these materials as teams around the world compete to develop the next generation of batteries, sometimes called super-batteries just for added exhilaration. The key factors in the hunt for improvements are energy density (more energy for less volume), safety and cost.

To take an example, in this video describing one company’s production of lithium-ion batteries for electric and hybrid vehicles, four elements are mentioned – lithium, for the anode, a metallic oxide for the cathode, a dry solid polymer electrolyte and a metallic current collector. This is confusing. In other videos the current collectors are made from two different metals but there’s no mention of this here. Also in other videos, such as this one, the anode is made from layered graphite and the cathode is made from a lithium-based metallic oxide. More importantly, I was shocked to hear of the electrolyte material as I thought that solid electrolytes were still at the experimental stage. I’m on a steep and jagged learning curve. Fact is, I’ve had a mental block about electricity since high school science classes, and when I watch geeky home-made videos talking of volts, amps and watts I have no trouble thinking of Alessandro Volta, James Watt and André-Marie Ampère, but I have no idea of what these units actually measure. So I’m going to begin by explaining some basic concepts for my own sake.

Amps

Metals are different from other materials in that electrons, those negatively-charged sub-atomic particles that buzz around the nucleus, are able to move between atoms. The best metals in this regard, such as copper, are described as conductors. However, like-charged electrons repel each other so if you apply a force which pushes electrons in a particular direction, they will displace other electrons, creating a near-lightspeed flow which we call an electrical current. An amp is simply a measure of electron flow in a current, 1 ampere being 6.24 x 10¹8 (that’s the power of eighteen) per second. Two amps is twice that, and so on. This useful videoprovides info on a spectrum of currents, from the tiny ones in our mobile phone antennae to the very powerful ones in bolts of lightning. We use batteries to create this above-mentioned force. Connecting a battery to, say, a copper wire attached to a light bulb causes the current to flow to the bulb – a transfer of energy. Inserting a switch cuts off and reconnects the circuit. Fuses work in a similar way. Fuses are rated at a particular ampage, and if the current is too high, the fuse will melt, breaking the circuit. The battery’s negative electrode, or anode, drives the current, repelling electrons and creating a cascade effect through the wire, though I’m still not sure how that happens (perhaps I’ll find out when I look at voltage or something).

Volts

So, yes, volts are what push electrons around in an electric current. So a voltage source, such as a battery or an adjustable power supply, as in this video, produces a measurable force which applied to a conductor creates a current measurable in amps. The video also points out that voltage can be used as a signal, representing data – a whole other realm of technology. So to understand how voltage does what it does, we need to know what it is. It’s the product of a chemical reaction inside the battery, and it’s defined technically as a difference in electrical potential energy, per unit of charge, between two points. Potential energy is defined as ‘the potential to do work’, and that’s what a battery has. Energy – the ability to do work – is a scientific concept, which we measure in joules. A battery has electrical potential energy, as result of the chemical reactions going on inside it (or the potential chemical reactions? I’m not sure). A unit of charge is called a coulomb. One amp of current is equal to one coulomb of charge flowing per second. This is where it starts to get like electrickery for me, so I’ll quote directly from the video:

When we talk about electrical potential energy per unit of charge, we mean that a certain number of joules of energy are being transferred for every unit of charge that flows.

So apparently, with a 1.5 volt battery (and I note that’s your standard AA and AAA batteries), for every coulomb of charge that flows, 1.5 joules of energy are transferred. That is, 1.5 joules of chemical energy are being converted to electrical potential energy (I’m writing this but I don’t really get it). This is called ‘voltage’. So for every coulomb’s worth of electrons flowing, 1.5 joules of energy are produced and carried to the light bulb (or whatever), in that case producing light and heat. So the key is, one volt equals one joule per coulomb, four volts equals 4 joules per coulomb… Now, it’s a multiplication thing. In the adjustable power supply shown in the video, one volt (or joule per coulomb) produced 1.8 amps of current (1.8 coulombs per second). For every coulomb, a joule of energy is transferred, so in this case 1 x 1.8 joules of energy are being transferred every second. If the voltage is pushed up to two (2 joules per coulomb), it produces around 2 amps of current, so that’s 2 x 2 joules per second. Get it? So a 1.5 volt battery indicates that there’s a difference in electrical potential energy of 1.5 volts between the negative and positive terminals of the battery.

Watts

A watt is a unit of power, and it’s measured in joules per second. One watt equals one joule per second. So in the previous example, if 2 volts of pressure creates 2 amps of current, the result is that four watts of power are produced (voltage x current = power). So to produce a certain quantity of power, you can vary the voltage and the current, as long as the multiplied result is the same. For example, highly efficient LED lighting can draw more power from less voltage, and produces more light per watt (incandescent bulbs waste more energy in heat).

Ohms and Ohm’s law

The flow of electrons, the current, through a wire, may sometimes be too much to power a device safely, so we need a way to control the flow. We use resistors for this. In fact everything, including highly conductive copper, has resistance. The atoms in the copper vibrate slightly, hindering the flow and producing heat. Metals just happen to have less resistance than other materials. Resistance is measured in ohms (Ω). Less than one Ω would be a very low resistance. A mega-ohm (1 million Ω) would mean a very poor conductor. Using resistors with particular resistance values allows you to control the current flow. The mathematical relations between resistance, voltage and current are expressed in Ohm’s law, V = I x R, or R = V/I, or I = V/R (I being the current in amps). Thus, if you have a voltage (V) of 10, and you want to limit the current (I) to 10 milli-amps (10mA, or .01A), you would require a value for R of 1,000Ω. You can, of course, buy resistors of various values if you want to experiment with electrical circuitry, or for other reasons.

That’s enough about electricity in general for now, though I intend to continue to educate myself little by little on this vital subject. Let’s return now to the lithium-ion battery, which has so revolutionised modern technology. Its co-inventor, John Goodenough, in his nineties, has led a team which has apparently produced a new battery that is a great improvement on ole dendrite-ridden lithium-ion shite. These dendrites appear when the Li-ion batteries are charged too quickly. They’re strandy things that make their way through the liquid electrolyte and can cause a short-circuit. Goodenough has been working with Helena Braga, who has developed a solid glass electrolyte which has eliminated the dendrite problem. Further, they’ve replaced or at least modified the lithium metal oxide and the porous carbon electrodes with readily available sodium, and apparently they’re using much the same material for the cathode as the anode, which doesn’t make sense to many experts. Yet apparently it works, due to the use of glass, and only needs to be scaled up by industry, according to Braga. It promises to be cheaper, safer, faster-charging, more temperature-resistant and more energy dense than anything that has gone before. We’ll have to wait a while, though, to see what peer reviewers think, and how industry responds.

Now, I’ve just heard something about super-capacitors, which I suppose I’ll have to follow up on. And I’m betting there’re more surprises lurking in labs around the world…

 

How will the super-duper Tesla battery work? And more on the price of electricity

(this is reblogged from the new ussr illustrated, first published July 19 2017)

Image: Thermo Fisher Scientific Inc.

I received an email the other day from the Australia Insitute. I don’t know how that happened, I’ve never heard of the organisation. Apparently it’s Australia’s most influential progressive think-tank (self-described) and apparently I subscribed to it recently while in a barely conscious state. All good.

Anyway the topic was timely: ‘Rising Energy Bills: Blame Gas’.

In a very recent post I quoted from a few apparently reliable sources on the reason for South Australia’s very high electricity prices. Unfortunately there wasn’t too much agreement among them, though at least none of them blamed renewable energy. But neither did any of them blame gas, though one did point a finger at wholesale pricing. The Australia Institute’s email put it thus:

Yesterday, we released the latest Electricity Update of the National Energy Emissions Audit for July 2017. The report revealed a stunning correlation between domestic electricity prices and gas prices — particularly in South Australia — despite gas making up only 10 percent of electricity generation.

So this is a subject I need to return to – in my next post. This post will focus on batteries and storage.

Neoen, a French renewable energy company, is building a 315MW, 99 turbine wind farm near Jamestown in South Australia. Connected to this project will be an array of Tesla’s lithium ion Powerpack batteries. According to this ABC News article:

The array will be capable of an output of 100 megawatts (MW) of power at a time and the huge battery will be able to store 129 megawatt hours (MWh) of energy so, if used at full capacity, it would be able to provide its maximum output for more than an hour.

It will be a modular network, with each Powerpack about the size of a large fridge at 2.1 metres tall, 1.3m long and 0.8m wide. They weigh in at 1,200 kilograms each.

It will have just slightly more storage than the next biggest lithium battery, built by AES this year in southern California.

But Tesla’s 100 MW output would be more than three times larger than the AES battery and five times larger than anything Tesla has built previously.

I’m no electrochemist, but a nice scrutiny of these sentences identifies a clear distinction between output and storage. And the output of this planned battery is the pioneering aspect.

So here’s a very basic summary of how a rechargeable lithium ion battery works. Each battery (and they vary hugely in size) is made up of a number of cells, each a battery in itself. On opposite sides of the cell are conductive surfaces, aka current collectors, one of aluminium and the other of copper. Inside and joined to these surfaces are electrodes, the positive cathode and the negative anode. The cathode is made from a lithium metal oxide such as lithium cobalt oxide or lithium iron phosphate, which needs to have the purest, most uniform composition for maximum performance and longevity. The negative anode is made from graphite, a layered form of carbon. The layered structure allows the lithium ions (Li+) created by the current to be easily stored at and removed from the carbon surface. Between these electrodes, filling the cell, is an electrolyte fluid through which lithium ions flow from one electrode to the other, which charges and discharges the cell. Again the purity of this fluid is a vital factor (research is being done to come up with a form of solid electrolyte). Between the two electrodes is an insulating plastic separator, essential to keep the electrodes separate and prevent short-circuiting. This plastic membrane allows the lithium ions to pass through it. The battery is charged when the lithium ions have passed through the separator and become attached to and stored in the layered graphite of the anode. The battery is discharged by reversing the flow.

Lithium ion batteries are found not only in Tesla Powerpacks but generally in electric car batteries and many other devices such as my own iPhone and iPad. They’re lighter and have much less energy density than lead-acid batteries. The technology of lithium ion batteries is described in a number of useful online videos, of which the most comprehensive, I think, is a webinar from the American Chemistry Society (ACS), essentially an interview with Dee Strand, a lithium ion battery specialist and expert. Her talk also provides interesting ideas on how these types of batteries can be improved.

So a fully-charged cell has stored energy, and a discharging cell is producing output. There are variations in lithium ion battery technology, for example variations in the electrode materials, the electrolyte composition and the like, so we don’t know precisely what Tesla will be using for the South Australian battery system, but we have a fair idea.

In any case, there seems no obvious reason why this proven technology can’t be scaled up to meet the sort of need that was identified after last September’s state blackout. Now we just have to wait and see whether Musk will lose his bet regarding completion time come December.

Refs and info

http://www.tai.org.au/

http://www.abc.net.au/news/2017-07-07/what-is-tesla-big-sa-battery-and-how-will-it-work/8688992

https://www.thermofisher.com/content/dam/tfs/ATG/CMD/cmd-documents/sci-res/pub/comm/env/AR-Lithium-Ion-Battery-Degradation-RandD-Mag-042214.pdf

http://www.abc.net.au/news/2017-07-07/sa-to-get-worlds-biggest-lithium-ion-battery/8687268

Just type in ‘lithium ion battery’ in youtube

What’s Weatherill’s plan for South Australia, and why do we have the highest power prices in the world? Oh, and I should mention Elon Musk here – might get me more hits

(this is reblogged from the new ussr illustrated, first published July 14 2017)

just a superhero pic to rope people in

I’ve written a few pieces on our electricity system here in SA, but I don’t really feel any wiser about it. Still, I’ll keep having a go.

We’ve become briefly famous because billionaire geek hero Elon Musk has promised to build a ginormous battery here. After we had our major blackout last September (for which we were again briefly famous), Musk tweeted or otherwise communicated that his Tesla company might be able to solve SA’s power problems. This brought on a few local geek-gasms, but we quickly forgot (or I did), not realising that our good government was working quietly behind the scenes to get Musk to commit to something real. In March this year, Musk was asked to submit a tender for the 100MW capacity battery, which is expected to be operational by the summer. He has recently won the tender, and has committed to constructing the battery in 100 days, at a cost of $50 million. If he’s unsuccessful within the time limit, we’ll get it for free.

There are many many South Australians who are very skeptical of this project, and the federal government is saying that the comparatively small capacity of the battery system will have minimal impact on the state’s ‘self-imposed’ problems. And yet – I’d be the first to say that I’m quite illiterate about this stuff, but if SA Premier Jay Weatherill’s claim is true that ‘battery storage is the future of our national energy market’, and if Musk’s company can build this facility quickly, then it’s surely possible that many batteries could be built like the one envisaged by Musk, each one bigger and cheaper than the last. Or have I just entered cloud cuckoo land? Isn’t that how technology tends to work?

In any case, the battery storage facility is designed to bring greater stability to the state’s power network, not to replace the system, so the comparisons made by Federal Energy Minister Josh Frydenberg are misleading, probably deliberately so. Frydenberg well knows, for example, that SA’s government has been working on other solutions too, effectively seeking to becoming independent of the eastern states in respect of its power system. In March, at the same time as he presented plans for Australia’s largest battery, Weatherill announced that a taxpayer-funded 250MW gas-fired power plant would be built. More recently, AGL, the State’s largest power producer and retailer, has announced  plans to build a 210MW gas-fired generator on Torrens Island, upgrading its already-existing system. AGL’s plan is to use reciprocating engines, which executive general manager Doug Jackson has identified as best suited to the SA market because of their ‘flexible efficient and cost-effective synchronous generation capability’. I heartily agree. It’s noteworthy that the AGL plan was co-presented by its managing director Andy Vesey and the SA Premier. They were at pains to point out that the government plans and the AGL plan were not in competition. So it does seem that the state government has made significant strides in ensuring our energy security, in spite of much carping from the Feds as well as local critics – check out some of the very nasty naysaying in the comments section of local journalist Nick Harmsen’s articles on the subject (much of it about the use of lithium ion batteries, which I might blog about later).

It’s also interesting that Harmsen himself, in an article written four months ago, cast serious doubt on the Tesla project going ahead, because, as far as he knew, tenders were already closed on the battery storage or ‘dispatchable renewables’ plan, and there were already a number of viable options on the table. So either the Tesla offer, when it came (and maybe it got in under the deadline unbeknown to Harmsen), was way more impressive than others, or the Tesla-Musk brand has bedazzled Weatherill and his cronies. It’s probably a combo of the two. Whatever, this news is something of a blow to local rivals. What is fascinating, though is how much energetic rivalry, or competition, there actually is in the storage and dispatchables field, in spite of the general negativity of the Federal government. It seems our centrist PM Malcolm Turnbull is at odds with his own government about this.

So enough about the Tesla-Neoen deal, and associated issues, which are mounting too fast for me to keep up with right now. I want to focus on pricing for the rest of this piece, because I have no understanding of why SA is now paying the world’s highest domestic electricity prices, as the media keeps telling us.

According to this Sydney Morning Herald article from nearly two years ago, which of course I can’t vouch for, Australia’s electricity bills are made up of three components: wholesale and retail prices, based on supply and demand (39% of cost); the cost of poles and wires (53%); and the cost of environmental policies (8%). The trio can be simplified as market, network and environmental costs. Market and network costs vary from state to state. The biggest cost, the poles and wires, is borne by all Australian consumers (at least all on the grid), as a result of a massive $45 billion upgrade between 2009 and 2014, due to expectations of a continuing rise in demand. Instead there’s been a fall, partly due to domestic solar but in large measure because of much tighter and more environmental building standards nationwide as part of the building boom. The SMH article concludes, a little unexpectedly, that the continuing rise in prices can only be due to retail price hikes, at least in the eastern states, because supply is steady and network costs, though high, are also steady.

A more recent article (December 2016) argues that a rising wholesale price, due to the closure of coal-fired power stations in SA and Victoria and higher gas prices, is largely responsible. Retail prices are higher now than when the carbon tax was in place in 2013.

This even recenter article from late March announces an inquiry by the Australian Competition and Consumer Commission (ACCC) into retail pricing of electricity, which unfortunately won’t be completed till June 30 2018, given its comprehensive nature. It also contains this telling titbit:

A report from the Grattan Institute released earlier in March found a decade of competition in the market had failed to deliver better deals for customers, with profit margins on electricity bills much higher than for many other industries.

However, another article published in March, and focusing on SA’s power prices in particular (it’s written by former SA essential services commissioner Richard Blandy), takes an opposing view:

Retailing costs are unlikely to be a source of rapidly rising electricity prices because they represent a small proportion of final prices to consumers and there is a high level of competition in this part of the electricity supply chain. Energy Watch shows that there are seven electricity retailers selling electricity to small businesses, and 12 electricity retailers selling electricity to households. Therefore, price rises at the retail level are likely to be cost-based.

Blandy’s article, which looks at transmission and distribution pricing, load shedding and the very complex issue of wholesale pricing and the National Energy Market (NEM), needs at least another blog post to do justice to. I’m thinking that I’ll have to read and write a lot more to make sense of it all.

Finally, the most recentest article of only a couple of weeks ago quotes Bruce Mountain, director of Carbon and Energy Markets, as saying that it’s not about renewables (SA isn’t much above the other states re pricing), it’s about weak government control over retailers (could there be collusion?). Meanwhile, politicians obfuscate, argue and try to score points about a costly energy system that’s failing Australian consumers.

I’ll be concentrating a lot on this multifaceted topic – energy sources, storage, batteries, pricing, markets, investment and the like, in the near future. It exercises me and I want to educate myself further about it. Next, I’ll make an effort to find out more about, and analyse, the South Australian government’s six-point plan for our energy future.

References and more reading for masochists

http://www.abc.net.au/news/2017-03-10/tesla-boss-elon-musk-pledges-to-fix-sas-electricity-woes/8344084

http://www.adelaidenow.com.au/business/sa-government-announces-who-will-build-100mw-giant-battery-as-part-of-its-energy-security-plan/news-story/9f83072547f41f4f5556477942168dd9

http://www.smh.com.au/business/sunday-explainer-why-is-electricity-so-expensive-20150925-gjvdrj.html

http://www.skynews.com.au/business/business/market/2017/03/27/accc-to-find-out-why-power-prices-are-so-high.html

http://www.adelaidenow.com.au/news/south-australia/south-australia-will-have-highest-power-prices-in-the-world-after-july-1-increases/news-story/876f9f6cefce23c62395085c6fe0fd9f

http://indaily.com.au/news/business/analysis/2017/03/07/why-sas-power-prices-are-so-high-and-the-huge-risks-of-potential-fixes/

http://www.theaustralian.com.au/opinion/columnists/graham-richardson/jay-weatherill-must-come-clean-on-elon-musks-battery-deal/news-story/f471b33ebdf140a71b41e0b0bea7894f

http://www.news.com.au/technology/environment/climate-change/why-higher-electricity-prices-are-inevitable/news-story/042712e35c08bf798ed993d13ee573ea

is wind power prohibitively expensive? apparently not

(this is reblogged from the new ussr illustrated, first published July 3 2017)

that’s a bloody big blade

Recently I heard retiring WA liberal senator Chris Back being interviewed, mainly on funding for Catholic schools, on ABC’s breakfast program. He was threatening to cross the floor on the Gonski package, but while he was at it he took a swipe at wind power, claiming it was heavily subsidised and not cost effective. Unfortunately I’ve not been able to find the whole interview online, to get his exact words, but as someone interested in renewables, and living in a state where wind power is prominent, I want to look more carefully at this issue.

On googling the question I’ve immediately been hit by link after link arguing that wind power is just too expensive. Is this a right-wing conspiracy? What are the facts? As I went deeper into the links – the second and third pages – I did become suspicious, as attacks on wind power spread to solar power and renewable energy in general. It seems there’s either a genuine backlash or there’s some manipulating going on. In any case it seems very difficult to get reliable, unbiased data one way or another on the cost-effectiveness of this energy source.

Of course, as with solar, I’m always hearing that wind power is getting cheaper. Thoughts off the top of my head: a standard wind farm of I don’t know how many units would be up-front quite expensive, though standardised, ready-tested designs will have brought per unit price down over the years. Maintenance costs, though, would be relatively cheap. And maybe with improved future design they could generate power at higher wind speeds than they do now. They seem to be good for servicing small towns and country regions. How they work with electricity grids is largely a mystery to me. There’s a problem with connecting them to other energy sources, and they’re not reliable enough (because the wind’s not reliable enough) to provide base-load power. I don’t know if there’s any chance of somehow storing excess energy generated. All of these issues would affect cost.

I also wonder, considering all the naysayers, why hard-headed governments, such as the Chinese, are so committed to this form of energy. Also, why has the government of Denmark, a pioneering nation in wind power, backed away from this resource recently, or has it? It’s so hard to find reliable sources on the true economics of wind power. Clearly, subsidies muddy the water, but this is true for all energy sources. It’s probably quixotic to talk about the ‘real cost’ of any of them.

Whatever the cost, businesses around the world are investing big-time in wind and other forms of renewable energy. In the US, after the bumbling boy-king’s highly telegraphed withdrawal from the Paris agreement, some 900 businesses and investors, including many of the country’s largest firms, signed a pledge to the UN that there were still ‘in’. The biggest multinational companies are not only jumping on the bandwagon, they’re fighting to drive it, creating in the process an unstoppable global renewable energy network.

The Economist, an American mag, had this to say in an article only recently:

In America the cost of procuring wind energy directly is almost as cheap as contracting to build a combined-cycle gas power plant, especially when subsidies are included…. In developing countries, such as India and parts of Latin America and the Middle East, unsubsidised prices at solar and wind auctions have fallen to record lows.

Australia’s current government, virtually under siege from its conservative faction, is having a hard time coming to terms with these developments, as Chris Back’s dismissive comments reveal, but the direction in which things are going vis-à-vis energy supply is clear enough. Now it’s very much a matter of gearing our electricity market to face these changes, as soon as possible. Without government support this is unlikely to happen, but our current government is more weakened by factionalism than ever.

Australia is 17th in the world for wind power, with a number of new wind farms becoming operational in the last year or so. South Australia’s push towards wind power in regional areas is well known, and the ACT is also developing wind power in its push towards 100% renewable energy by 2020. Australia’s Clean Energy Councilprovides this gloss on the wind energy sector which I hope is true:

Technological advances in the sector mean that wind turbines are now larger, more efficient and make use of intelligent technology. Rotor diameters and hub heights have increased to capture more energy per turbine. The maturing technology means that fewer turbines will be needed to produce the same energy, and wind farms will have increasingly sophisticated adaptive capability.

The US Department of Energy website has a factsheet – ‘top 10 things you didn’t know about wind power’, and its second fact is bluntly stated:

2. Wind energy is affordable. Wind prices for power contracts signed in 2015 and levelized wind prices (the price the utility pays to buy power from a wind farm) are as low as 2 cents per kilowatt-hour in some areas of the country. These rock-bottom prices are recorded by the Energy Department’s annual Wind Technologies Market Report.

As The Economist points out, in the article linked to above, Trump’s ignorant attitude to renewables and climate science will barely affect the US business world’s embrace of clean energy technology. I’m not sure how it works, but it seems that the US electricity system is less centralised than ours, so its states are less hampered by the dumbfuckery of its national leaders. If only….