Large banks take a lot of flak for, well, undeniably taking some risky decisions that are a contributing factor to the economic times of difficulty that we are today. It’s easy to pick on them for other developments in the energy sector too, for example their reluctance to invest in renewables, and their role in investing in ‘unconventionals’ such as tar sand oil and shale gas. From the left, this causes protest and outrage. Aren’t we supposed to be reducing our carbon emissions? Don’t these techniques cause environmental concerns?
Ironically, of course, this is all about the risk. Renewables are ‘new’ and there’s uncertainty surrounding the future of global energy. While the argument of climate change and impact on future generations is compelling, fundamentally the problem is a matter of economics and risk of a return on investment. If the fuels in the ground are economically extractable, someone will extract them. Call me a realist, but that’s the primary factor that drives these investment decisions. If we want to change this we have to change the rules of the game.
1) Renewables and nuclear research. Lowering the cost of alternative technologies reduces the competitiveness of oil and gas extraction. There are some technologies (solar in Silicon Valley) for example, that are already nearly at grid parity with conventional generation.
2) Carbon taxes. Recognising that emitting carbon is bad and applying a value to this. As a result, the economic value of extracting fossil fuels relative to renewables falls. The difficulty is implementing such a scheme fairly. The European emissions trading scheme set up to do exactly this has run into all sorts of teething troubles thanks to too many permits being issued (largely due to an unplanned recession - which does a splendid job of cutting down on our carbon emissions) and hence a very low carbon price which has not provided certainty and thus limited any investment in carbon reduction. A higher carbon price floor would help in the future here, and we look to set to get this given that a £30/t floor is to be in place by 2020.
3) Regulatory certainty. The barrier to investment in renewables is often surrounding policy. Knowing that the government will not move the goalposts - the government’s 2011unplanned change to feed in tariffs is a key example of this uncertainty and and how it can damage an industry. Choose a plan, and stick with it.
Resolve the above three issues, and you solve the fundamental problem with the energy game. If you can do that, the players will adapt.
(If I lost you with the title of this piece, I thought of it in mind of HBO’s show The Wire. Although quite a different type of political commentary of impoverished, drug rife communities in America, the show draws some interesting parallels to the energy challenge; how ‘players’ are mere cogs in a machine they have no control of.)
I saw this tweet by Roger Helmer a while ago and thought was worth responding to, and it’s only a few months later that I’ve found the time to get round to commenting on it. For those of you who don’t know Roger, he’s a European Parliament member, formerly of the Conservative party, but who switched to UKIP because of closer alignment to his views. He’s particularly outspoken on Europe and Climate change.
A number of his tweets are on the subject of renewables, and whether by design or by accident are often factually baseless, misinformed or cherry picked. There are certainly some significant challenges to overcome regarding the integration of renewable energy, and I fully acknowledge that. As I research into this very area, I have a practical grasp of some of the political, economic, social and technical problems that need to be solved, but often not the ones that he informs his audience of.
I’ve taken a relatively recent example in the above tweet – Roger links to a piece by the Global Warming Policy Foundation . The GWPF is anti-renewable lobbying think tank, with a track record of producing reports that have subsequently been debunked. While they make some seemingly valid points, their reports do not support strong statements like the one Roger paraphrases in his tweet. The phrase “Why let the facts get in the way of a good story?” springs to mind.
Let’s look at the accusation in that tweet that prompted me to write something. Namely, that renewables don’t reduce CO2emissions. I’ve dutifully done a bit of digging into the method and found that the relevant section of the GWPF report argues that:
“Wind power is intermittent and requires backup sources of power – either gas or coal. These backup sources achieve much lower levels of thermal efficiency – defined as the proportion of the energy content of the fuel that is converted into electricity - than conventional power plants using the same fuel which operate all or most of the time. The loss in thermal efficiency is even greater if the backup sources have to run for extended periods as spinning reserve, using fuel but not delivering power to the grid, in order to smooth fluctuations in either demand or supply from wind sources. Hence, the loss in thermal efficiency when plants run as backup sources may outweigh the reduction in the total amount of power generated from fossil fuels when wind generation is added to the system.”
Now there is an underlying truth to this paragraph, but a lot of questionable content too. I have previously covered why wind is variable, not intermittent, and that it doesn’t require dedicated back up. So has a large body of literature by a number of authors, which I am happy to provide if interested. So let’s start by not overstating the problem. The spinning reserve on an electricity system is there to support all units on the grid, including other fossil fuel plants which can trip out and not just wind.
The observation about power plant thermal efficiency is entirely correct. A power plant operating at a lower load (producing fewer MWs of electricity than its rated output) will be at a lower efficiency, and hence its emissions (measured by the standard metric of kgCO2eq) will be higher. However “much lower…efficiency” is a qualitative statement which is used to underpin the argument that these will outweigh the savings from wind. Astute readers will note that Dr. Hughes who wrote this report uses the word “may”. This qualified version appears to have been lost in translation by Mr. Helmer when he tweeted it. I wonder why.
It is entirely possible that Dr. Hughes, who wrote the report, did not have the data to hand in order to calculate whether or not the emissions increase from part loaded power plants would outweigh the benefits of renewables. I however, can. So let’s go one better and quantify this and see if this is the case or not.
<Warning, maths ahead… but its straightforward GCSE stuff, I promise>
Below is the heat rate curve for a typical fossil fuel plant. Power plant operators think of things in terms of heat rate and not efficiency, but a heat rate curve is fancy sounding way of describing the efficiency of a power plant at different levels of power production. The thing to remember is that a low heat rate is good and equates to higher efficiency, and vice versa.
The curve below shows how at lower loads, it requires more energy to produce a unit of electricity, and how a power plant is at its most efficient when it is close to its full generation output. The difference between the heat rate at its minimum generation (110MW) and its average output (around 174MW) is about 15%.
Make sense so far? In other words you require 15% more energy to generate a unit of electricity at this low load rather than the average load.
Now, let’s qualify this with an example with and without wind. The average grid carbon intensity of coal is around 1,015kgCO2eq/MWh., so when a coal plant is operating at 174MW its total emissions are roughly:
1015kgCO2eq/MWh * 174MW = 177tCO2eq/h
If this plant was held right back at its minimum generation of 110MW to make room for an additional 64MW of wind, the resultant emissions of the plant would increase 15%. The net emissions of a system with this level of wind would hence be:
1015kgCO2eq/MWh * 1.15 * 110 = 128tCO2eq/h
In summary, despite the reduced plant efficiency, wind still has a net positive saving of 177-128 = 49 fewer tonnes of carbon dioxide being pumped up into the atmosphere every hour. If we wanted to be really rigorous there are some very small emissions associated with wind production too, but not to a level that would significantly alter this outcome.
So we can safely declare this tweet debunked. Wind energy clearly does reduce CO2 emissions.
By way of PostScript to this blog entry, I would say there’s a need to give scientists a platform to explain their research when the media grab a hold of something and misinterpret it. Little exercises like the one I just carried out are really vital for debunking incorrect ‘science’ and it’s important that we see more of them.
The problem is not so much lack of research or understanding, it is something really quite endemic in the media, where scientific studies are occasionally misinterpreted or skewed to support a particular view point, even when the original research may have a sound basis and be published in good upstanding peer-reviewed journals. This is something Ben Goldacre has written in his book Bad Science and I strongly recommend giving it a read if you’re interested in arming yourselves against some of the ways science is misused in the media.
[Invited contribution to National Grid’s Powering Britain’s Future campaign]
Any solution to our future energy challenge has to be technically workable, economically tenable and socially viable. With the growth of renewable energy coming from variable resources such as wind energy, a variety of ways of managing an inherently more variable level of electricity supply have been suggested.
A lot of hope is pinned on demand side management; altering the historically rigid pattern of demand to suit the profile of supply, particularly as there is a move to electrify transport and heating demand. This would require interaction between the kinds of things we use electricity in (fridges, heating systems etc.) in what is referred to almost universally now in research as a smart grid. When the energy supply is high (due to high wind generation for example), these devices would be optimised to turn on and draw energy, storing it in effect by keeping your fridge cold, topping up your hot water tank and so forth. When the energy supply is low (wind generation drops), these devices would be instructed not to draw energy from the grid for a certain amount of time. As your fridge and hot water tank are insulated well, it takes a long time for them to start to change temperature. This allows you to alter demand to match supply, and all is well and good with the world; the lights stay on, you use renewables, and avoid using depleting and carbon burning fossil fuels as much as possible. World saved, Al Gore is a happy bunny.
The challenge in this sort of solution is only partly technical. It’s also social and behavioural. I see behavioural change as a problem that cannot be fully overcome. Humans have a funny knack of not liking change, and this has confounded a lot of well thought out technical solutions in the past. It’s the reason a lot of efforts into designing low carbon buildings are struggling to meet their design values; people use them in a way they aren’t supposed to.
One of the areas of huge potential for smart grids is to be the take-off of the plug in electric vehicle (EV) market. A large number of cars, with a large number of batteries make a huge aggregated store for excess renewable energy when we have it, and supply when we do not. However, the principle is very difficult to get off the ground – why? Firstly, infrastructure. Conventional internal combustion (IC) engine cars on average have a tank of 60-70l (around 15 gallons), and the best cars we’re producing can do over 100MPG. That’s a 1,500 mile range (ok, so an average car does 30MPG but you get the point), which is plenty for reaching a petrol station, filling up a petrol tank and shooting off again. The plug in EVs on the market today do 35-90miles on a full battery, and even fast charge batteries need 1.5 hours to fill up completely, and that’s if you can find a charge point, because while there are plenty of petrol stations, there aren’t all that many charge points.
This comparison is a little unfair, as it is worth stating that the idea of the phased introduction of plug in EVs is that most families have two cars (if you accept this is narrowing your market down) – one for long range travel, and one for regular driving for work, the school run and the shops – after all some 95% of journeys are under 25 miles. There’s also talk of biofuel/electric hybrids (think of the future along Toyota Prius lines) giving the best of both worlds; range and not having to worry if you don’t have time to charge, but this is limited due to the size/weight of batteries and the need to still find room for a combustion engine and a fuel tank. The issues surrounding biofuels are also another whole matter for discussion.
The facts around electric vehicles suggest to me that the plug in approach is a nonstarter because it requires people to accept that they have to treat this kind of car differently. The charging infrastructure doesn’t exist yet (chicken and egg situation this – a proper infrastructure for EVs won’t exist until there are EVs, and vice versa). The issue of having to wait for your car to charge and the limited range makes it clear that EVs are impractical for long distance travel. Batteries are also a very expensive part of a car and the main reason why EVs cost a lot more up front than conventional IC cars. The running cost of EVs on electricity is very low relative to the running cost of an IC car on petrol or diesel.
Finally, to be used on a smart grid at all plug in EVs are expected to require users to sign up to special tariffs that give permission for the grid to charge and discharge the batteries in order to balance supply and demand. To make a meaningful difference, this has to be from a lot of people to be able to cope with significant quantities of variable supply renewable energy on the electricity grid. These are a really significant part of the problem, as electrifying our cars without helping decarbonise our grid will increase our overall consumption of fossil fuels. Burning diesel in your car directly is more efficient than burning diesel to generate electricity to power your car because of the losses in the process – electrifying cars ONLY works if your electricity comes from low carbon sources.
If you add all these individual components up, it comes to quite a lot to ask from people who are used to the independence and flexibility of IC travel. If we can’t get acceptance then we have to shelve this solution as one that is technically workable, economically tenable but not socially viable.
Let’s sum up the problems with plug in EVs:
· Car range not suited to all types of journey – only short distances
· Charge times – even fast ones don’t come close to a petrol fill up
· Lack of charge points for EVs, lack of EVs for charge points.
· Lack of smart grid infrastructure
· User acceptance: having to opt into being charged
· High up front cost of electric vehicles
· High adoption needed to decarbonise electricity for net benefit.
Seems a bit difficult to get around doesn’t it? However, in my opinion there is something that sweeps all of these problems aside and is entirely compatible with our existing infrastructure. What is it? Interchangeable batteries.
By this I mean having EV batteries you can swap out when they’ve run down. The charge up nightmare is avoided, as is the journey range issue. You can use the existing petrol station infrastructure for recharges and travel as much as you like. Without the battery coming as part of your car, the price of EVs is dramatically cheaper, so adoption rates go up. This solution also neatly steps round the user-smart grid acceptance issue, as companies that would be responsible for the vending of the batteries would also be responsible for their charging and conditioning (which would also be done to prolong asset life in a way that individual car owners may not). Having a large collection of batteries in one place (think local storage warehouses for regional petrol station resupply) also ensures that when the batteries are not on the road, they are in use helping to balance the grid. As this would be done commercially, there is direct value in providing capacity storage or ancillary service prevision to the grid, and the political and socially difficult smart grid rollout with differential tariffs (in a time when the government is demanding simplicity) is avoided.
In one fell swoop, the problems of EVs disappear and all the benefits remain.
The business opportunity for interchangeable EV batteries is there; the only truly significant hurdle to overcome is the need to standardise an interchangeable battery design that will work with future EVs on the market. Solve this, and the business opportunity solves itself.
My final argument against those who argue that 100% dedicated backupfor wind generation is necessary:
3) Variations in wind are to an extent predictable, and not instantaneous.
As already established in my last piece (It’s not reinventing the wheel), the system of balancing electricity generation already has a framework established to compensate for the loss of generation or deviation from the expected supply/demand balance. Often this achieved by part loading existing power plants (in other words running them at less than their maximum output). This allows those who control the system to increase or decrease their output in order to keep the whole delicate see-saw of electricity supply and demand matching.
Most of us experienced a trip at home when a light goes and the circuit breaks automatically, but at transmission scale the loss of a power plant is of megawatt or gigawatt scale. It is important to remember that these sort of trips are low probability, high impact event. It means the loss of a significant amount of power in a fraction of a second on the system. This very kind of intermittent power loss cannot be predicted in advance, yet sufficient measurements must be in place to ensure the system readdresses the balance very quickly or the result will very quickly be a loss of grid stability and force rolling blackouts.
If we now come back and think of wind generation and how it changes, its nature is very different. As opposed to being intermittent (as it is often cited), wind generation is variable because changes in wind generation vary more gradually.
Gigawatts of distributed wind do not get shed in an instant, as there is not a single point of failure like when a power plant trips, hence we have more time to respond to a moving weather front. Allowing for sufficient reserve is actually easier than for conventional power plants in this respect.
Furthermore, wind variability is also predictable. Although forecasts are still out on timing occasionally, generally the pattern and rate of change is correct.
Compensating for a gradual loss of generation that you know is coming is considerably easier than planning for a sudden shock loss of a large amount of power. When thinking about the challenge from this respect, the argument is completely flipped – if anything we need dedicated backup for our conventional generation more than for the wind added to the system!
Reason number two why wind generation on a large scale electricity system does not require 100% dedicated backup is:
2) Electricity systems already require balancing and backup.
This is a critical and often overlooked point. Whether or not variable generation is on an electricity system, there is a need to have generation in reserve to deal with in any deviations between demand and supply. This is not a new concept, it has been around from the early days of large scale electric power generation.
Demand is not always what it is predicted to be. Humans are creatures of habit, but occasionally we break our routines enough for system wide to deviate from its predictable pattern. Electricity supply is similarly not necessarily what we ask it to be. Generators sometimes cannot provide as much electricity as they are expected to, for a number of reasons. Sometimes maintenance periods can run over and a unit that was expected to be online cannot be synchronized to the grid. Sometimes faults develop during generation that reduces the power output of the unit, or more severe, a unit trips and all of its power is lost. Because this system of backup already exists, the marginal cost of additional backup is considerably reduced – the backup required for wind is already largely present for dealing with the loss of existing generation.
Ok, last post in this series.
We’ve now covered the problems with carrying on as we are in terms of generating electricity (basically, we can’t!), and have tackled two of the three technologies that can help us deal with this challenge. Finally, a little bit wiser hopefully, we are on to the technologies I originally wanted to discuss… renewables.
There are a huge number of renewable technologies, including:
· Onshore wind
· Offshore wind
· Solar PV
· Solar CSP
In the UK we are blessed with one of the best wind, wave and tidal resources in Europe, all forms of renewable energy that can be developed and exploited to our benefit. Renewable energy is a broad field, and not one technology, but an umbrella term for many different technologies with different respective advantages and characteristics.
Their common benefits are that they utilize naturally replenishing resources, rather than finite fossil fuels, or finite nuclear fuels. Their fuels, the wind, the waves, the tides, are all free. They are zero carbon, and provide a huge potential opportunity for manufacturing, innovation and growth. Anything else about them has to be said individually, as they have different characteristics that offer different drawbacks and benefits. To avoid cramming this all into one post, I will have to tackle these individually at one point or another in the future. For now, suffice to say these can work in a very complimentary way, and many technological developments can help some of their potential drawbacks.
So given the security of supply, fossil fuel scarcity and climate change concerns, we now have a much more compelling basis to consider alternative forms of generating electricity. We have three choices: Nuclear Power, Carbon Capture and Storage and, finally, Renewables.
I’ll dedicate my next few blog posts to these technologies in turn. I will not elaborate on how they work or debate them in detail; merely present the benefits and concerns with them. If you do wish to learn more, I’ll be happy to point you in the direction of any resources.
On to the final of our three arguments of why our fossil fuel based economy can’t continue, and perhaps the most fundamental of all. Even the skeptics of climate change and those unconcerned by security of supply find it difficult to argue with the fact that fossil fuels are a finite resource that will run out, potentially within our lifetime. Coal, gas and oil have all formed over millions of years, by the slow relentless buildup of heat and pressure of many layers of geology. They cannot be replenished in our lifetimes. They will run out; the question is simply a matter of when.
Calculating how large the reserves of fossil fuels are in the subterranian world under our feet is an uncertain and imprecise art, and for this reason, estimates vary widely. It is normally quoted as an “X years supply remaining” figure, though of course this relies heavily on the assumptions that are made regarding future consumption patterns. All trends point upwards, given the rapid development of countries such as India and China.
It is widely accepted that there is substantial more coal than gas or oil that has not been tapped into, perhaps enough to last several hundred years. It is more labour intensive to extract, requiring extensive mining operations rather than wells, and it’s quality varies largely; there are many different types of coal, depending primarily on the age of the seam. The “best” coal, and the longest pressurized, is anthracite, which resembles a very hard rock, the weakest for use as a fuel is peat, which is still almost like a soil. These fuels all burn with very different qualities; poorer coals such as lignite and peat produce less energy and a lot more ash per unit burnt compared to anthracite.
Our oil and gas reserves look a lot less short lived than coal. Estimates of reserves vary considerably, and it is again very difficult to know how significant the resource we actually have is. Oil and gas come from deep under the earth’s surface, something we can only probe at. It is not a simple metric to measure, and most predictions involve statistically including reserves that we have not discovered (probable reserves) in addition to those we know we have (proven reserves). Depending how optimistic you are about finding new reserves, you get rather different answers regarding how much supply of oil we have left. Estimates are typically in the range of 50-70 years supply for both.
There is still considerable debate as to whether a world peak of oil production will occur, and whether a sharp decline will follow. Economists and oil companies argue that advances in exploration and adapting technology to unconventional fuels (e.g. shale oil fracking) will delay the peak and prevent a sharp decline, or even plateau it indefinitely, buying the world time to develop a technology to replace oil, whereas many geologists believe that the peak is imminent.
In either case, there is a matter of time running out that forces our hand… climate change, security of supply and scarcity of finite fossil fuels all mean we need to transition to producing electricity another way, and within only a few decades. No mean feat. Next time… what are our options?
Last time I discussed the first of the arguments for moving away from fossil fuel based generation, summarising that climate change, while certainly supported by a vast body of evidence, is not well communicated with the public and this has led to acceptance issues.
This time, we shall consider the second argument of those I identified in Part I, relating to security of supply.
Security of supply is a very serious sounding term, the likes of which is used by dour men in Westminster, wearing somber coloured suits, tutting quietly and beguiling the state of things. The term simply means ensuring that our electricity supply is not interrupted. That the lights stay on. Always.
Our economy depends on an uninterrupted supply of electricity. Our economy would not function without it. The stock market, the internet, motors… all run off this invisible supply, carried by transmission and distribution lines up and down the country. A blackout costs the economy billions. Worse still, it can cost lives.
If we accept the climate change argument, we already have a strong argument to move to sustainable, low carbon forms of energy. Even if we do not, there is a second valid concern regarding our dependency on other countries for the fuel we use. In the UK, we produce electricity with a lot of gas and coal. We have limited resources of gas and rely heavily on imports. Even though we do have coal reserves, we get a lot of it from other countries because it’s cheaper.
As fossil fuel resources become scarcer (or alternatively, more expensive to process, for example with shale gases), electricity prices will be forced to rise. Competition increases, and we will struggle to continue with a reliable supply of fuel. The Russia-Ukraine gas crisis of 2006 is a classic example of the danger of relying on one country for much of the fuel used in our power mix. If we rely on gas, and our gas is primarily piped from Russia, what happens if the supply is switched off? Security of supply. Tutting dour men in Westminster.
Food for thought, even for the climate skeptics. Next time: the final of the three main arguments; fossil fuel scarcity.
The argument that our earth’s climate is changing, and that this is due to our human activity, has been a point of discussion for many, many years.
Over time the strength of argument has grown, with more studies and more verification. There is a strong consensus of the scientific community that anthropogenic (human influenced) global warming is occurring, and that we need to sharply reduce our carbon emissions to limit the change to our climate that has been set into motion.
Sadly, scientists (with notable exceptions of characters such as Brian Cox and Robert Winston), have a poor track record at engaging with the general public, and explaining science. The job is often left to the media, whose job is to entertain as well as to inform.
Notable scandals and controversies, such as “climategate” undermine this consensus in the eye of the public. This is seized to political advantage, and climate change is presented as the need to change the way we change we think about our energy consumption as an unnecessary tax. A con.
If you investigate the University of East Anglia emails for yourself (Go on… I’ve linked it), you might be surprised to find there is nothing in fact to the hype of the media regarding the scandal. Of course, most of us do not have time to investigate these things for ourselves, and rely on the media to inform of us of current affairs. This is where the seeds of doubt are presented in our minds and why the climate change argument keeps re-emerging; consensus is boring. People don’t want to read about it.
This is a very difficult PR problem for the scientific community to overcome. We, as a community, need to be able to convey our research across more effectively.
If you are a climate skeptic, I would encourage you to look at the reports of the IPCC if you wish to delve into the science, and to watch Al Gore’s An Inconvenient Truth even if you are not. These set out the case for anthropogenic climate change a lot better than I ever could. Be wary also of the anti-climate science used to dispute these findings. Some are perfectly reputable studies, discovered by the media and use out of context to report something the scientist did not intend to be understood. Others are based on cherry picking evidence (case in point, the “Climategate” emails). Ben Goldacre’s Bad Science is an excellent resource to arm yourself against disputable techniques used in the anti-climate science camp, and indeed in all aspects of science.
That’s enough for this post. This is a big topic and one that could never be adequately addressed in a few paragraphs, but hopefully there’s enough food for thought there to go out and investigate if you find yourself doubting climate change because of what you have read in the media.