Archive for the ‘Energy technology’ Category

Professor Sir David MacKay FRS

I was sad to hear of the recent death of Professor Sir David MacKay. I had met him at a few events over the years, but his real impact on me was through his book Sustainable Energy: without the hot air.

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Hopefully everyone who reads this blog has also had the opportunity to read David’s book, if not I can highly recommend it. It is free to download here. The book is a wonderful tour of energy use, written in a language that everyone can understand. Most importantly, it seeks to challenge and correct the many assertions made about how quickly and easily we can change the energy system or how easy it would be to power everything from a particular source. Professor MacKay took exception to the loose talk and poor reporting around energy issues and sought to rectify it. In the opening lines of his book he notes;

Perhaps the worst offenders in the kingdom of codswallop are the people who really should know better – the media publishers who promote the codswallop – for example, New Scientist with their article about the “water-powered car.”

That single sentence sets the tone for a very entertaining and thoroughly informative deep dive into all things energy related, with the maths to back it up. He even delves into climate science and offers a wonderful analogy for why atmospheric carbon dioxide is rising when anthropogenic flows of the gas are so much smaller than natural flows (trees etc.). He compares the atmosphere to passport control at an airport!!

But the calculation that has stuck in my head over several years relates to hydroelectricity in the United Kingdom. I don’t know why I remember this story in particular, I am no more a hydroelectricity enthusiast than I am a nuclear enthusiast, but his explanation was just so elegant. Many people imagine that because it rains quite a bit in the UK that we ought to be able to power much of the country with hydro, particularly in Scotland where it is also quite hilly. Professor MacKay’s simple calculation involved the land area of the UK, the average rainfall, the average elevation and the wildly optimistic assumption (just to silence the optimists) that we would catch every drop of rain and then all the potential energy within that water as it drops from the point at which it initially hits the ground until it gets to sea level. The absolute upper limit for hydro comes out at less than 10 kWh/person/day, but the more realistic figure is <2 kWh/person/day. This is against energy demand of around 200 kWh/person/day. Actual hydro in the UK is just 0.2 kWh/person/day.

Sadly we have lost an inspiring energy enthusiast and an entertaining writer and speaker. RIP Professor.

The last few weeks have brought great excitement for electric vehicle (EV) enthusiasts with the announcement of the Tesla Model 3 and the subsequent filling of its order book with over 250,000 vehicles. With costs coming down and vehicle range improving, there appears to be real consumer interest in EVs, including battery electric, plug-in hybrid and hydrogen fuel cell types. The International Energy Agency has been following the development of EVs for some time now and an excellent info-graphic is available with a variety of useful deployment statistics for the period up to and including 2014.

IEA EV Infographic

But how quickly would EVs have to deploy to align with the ambition of the Paris Agreement, i.e. having the passenger vehicle sector reach nearly zero direct emissions early in the second half of this century? Such an outcome would be required to be on track to well below 2°C, with a shot at 1.5°C.

In the last 2-3 years EV growth rates have been in the range 50-100% per annum, but this is quite typical of a new technology with a very small base. As the base increases, year on year percentage growth slows down quickly, even as absolute production continues to increase.

The first goal for EV deployment is to reach an installed base of 20 million vehicles by 2020, or about 2% of the global fleet. This is the target set by the Electric Vehicle Initiative of the Clean Energy Ministerial, a global energy/environment Minister forum to promote policies and share best practices to accelerate the global transition to clean energy. The initiative seeks to facilitate the global deployment of EVs, including plug-in hybrid electric vehicles and fuel cell vehicles.

By the end of 2015 the global EV stock was heading towards 1.5 million , which gives just 5 years to produce another 18-19 million cars. That will require year on year growth rates of around 50% per annum into the 2020s, resulting in additional new production of some 1-2 million vehicles per annum, i.e. to reach total annual production of 6-7 million vehicles per annum in 2020 itself.  According to the IEA info-graphic, production in 2014 was around 300,000 per annum.

If growth at such rates could continue, with additional new production surpassing 4 million per annum throughout the balance of the 2020s and into the 2030s, then by 2035 the global EV stock could be at 500 million vehicles, or nearly a third of the total expected fleet. By this time absolute annual EV growth may be slowing, influenced by an outlook that sees EV production approaching that of global passenger vehicle production. This is assuming that there is no consumer resistance to EVs, even amongst those who love the roar of a finely tuned high powered internal combustion engine (ICE).

But even if production of EVs completely eclipses that of ICE vehicles, there remains the generational timespan to turn over the entire fleet. Even in Europe, the age distribution of vehicles is very broad, so we shouldn’t expect ICE vehicles to disappear overnight. The average age has also been rising, up from 8.4 to 9.7 years in Europe over the last decade. There is also a wide distribution, for example in the Netherlands in 2012, 41% of the passenger vehicle fleet was over 10 years old, but for the same year in Poland it was 71%.

Putting all the above together in a single chart, a very rapid and accelerated switch from ICE to EV could look something like the picture below. For the sake of the calculation, I have assumed the global fleet topping out around 1.7 billion vehicles in the 2060s, a number which is highly uncertain. For instance, just as EVs are beginning to make progress in the market, autonomous vehicles are possibly offering a completely different model for car ownership, which could see far fewer cars in the global fleet. The prospect of a much smaller market could start to send ripples through the entire investment chain, slowing the uptake of EVs considerably. Equally, if personal motoring progresses rapidly in developing countries, the fleet could be much larger in the second half of the century, which may also argue for an older fleet with ICE vehicles remaining on the road for much longer.

EV Stock

Simply because of fleet growth and existing production which currently totals 65-70 million vehicles per annum, maximum ICE stock isn’t reached until well into the 2020s, topping out at about 1.2 billion vehicles vs. 900 million today. ICE numbers return to current levels in the mid-2030s, but then decline to very low levels by the 2060s.

There are many other unknowns to factor in, such as the supply chain for the EV. Current battery technology calls for lithium, but prices over the last 18 months have risen. Some Chinese Lithium Hydroxide prices have risen over 100% in the last year but some market observers have noted the volatility and uncertainty surrounding this.

With the Tesla 3 appearing on the streets in 2017, but many other models from various manufacturers also being shown, the years ahead will only get more interesting for the passenger vehicle market.

The Connected Man

Back in September 1971, an article appeared in Scientific American on energy use. It remains very current today. Earl Cook was attempting to look at the limits to energy use and how that energy might be provided in a modern society. The article starts with the chart below that shows potential demand from various stages of human development.

Earl Cook Diagram

Today, we see human society spread right across the chart with substantial parts of the world in one of the versions of Agricultural Man, whilst many of us are in Technological Man. Global energy use stands at some 600 EJ, or about 80 GJ per person per annum whereas in 1971 the number was around 60 GJ. There are significant regional, national and even sub-national differences, with the USA at around 300 GJ and India at 30 GJ as two examples. It is also important to recognise that the Earl Cook chart applies more to the individual archetypes, rather than to national averages. At any point in time, the national average may include people in several categories and the individual demand may not be fully reflected in the national average if imports exceed exports in quantity or carbon intensity or both.

Cook pondered about where this energy might come from and what the limits of supply might be. Although resource constraint was a popular topic at the time (and another article in the same edition of the journal was by peak oil enthusiast M. King Hubbert), Cook concluded that environmental constraints may be more limiting than the resource itself. Although his focus was on more local environmental issues, his overall thinking was close to the mark as society now faces real constraints on emissions of carbon dioxide.

Yet we are far from done in terms of progression from Primitive Man to Technological Man.

Further on, Connected Man, which perhaps didn’t feature in Cook’s 1971 thinking, offers a very different outlook. Such a concept poses a real challenge – will Connected Man use even more energy than Technological Man with the introduction of a new Information category in the bar chart and further expansion within the other categories? Or perhaps Connected Man can break the trend above and bring such efficiency to the other categories that overall energy use per person falls, even as development progresses? That would be unprecedented (N.B. The Connected Man energy numbers are notional and for illustration purposes only).

Earl Cook Diagram (Connected Man)

Connected Man is starting to appear today, with the prospect of 20 billion connected devices comprising the Internet of Things as early as 2020. A trillion connected devices by 2050 would be a reasonable extrapolation from that; it represents less than 15% growth in such devices per annum. It may be much more than this, but the energy demanded by these is unlikely to be trivial, even as efficiency improves.

The real question is what such connectivity offers to the energy system as a whole? Can it also lower the energy use of Industrial Man as well as offering the prospect of leapfrog to a much lower energy demand end state than might have been anticipated for Technological Man? That might have a profound impact on expected global demand later in the century even as we collectively progress to Connected Man. Nevertheless, while 21st century efficiency will very likely temper eventual energy use per capita, particularly against Cook’s 1970s estimates, the premise of rising energy demand at a global level still stands.

Earl Cook Diagram (Connected Man +)

Solar thermal by the numbers

Early in February the King of Morocco, HE Mohammed VI, opened the first phase of what will eventually become a major solar energy facility in the centre of the country. On the same day, the King also laid the foundations for Phase 2. The project is a remarkable piece of engineering, with tracking parabolic mirrors reflecting and concentrating sunlight into a heating loop, which then transfers the energy into steam and ultimately electricity from turbines. The system also includes a molten salt energy storage system which provides 3 hours of turbine operation once the sun has set.

Noor Solar

The Noor Ouarzazate Concentrated Solar Complex is being developed 10 kms north-east of the city of Ouarzazate at the edge of Sahara Desert about 190 kms from Marrakesh. Phase One of the project involves the construction of a 160MW concentrated solar power (CSP) plant named Noor I, while Phase Two involves the construction of the 200MW Noor II CSP plant and the 150MW Noor III CSP plant. Phase Three will involve the construction of the Noor IV CSP plant.

The original cost of Noor I was estimated at about $1.1 billion, but various reports show that upwards of $2 billion has been spent, although a proportion of this must be for overall site development, roads, infrastructure etc. which will benefit all of the phases. A description of Phase II can be found on the World Bank website, with an estimated cost of $2.4 billion for construction and $300 million as a cost mitigation mechanism (i.e. to lower the cost of the electricity produced during the initial years of operation).

The initial 160 MW project has a net capacity of 143 MW, producing some 370 GWh of electricity output. This equates to a capacity factor of nearly 30% which is high for solar, but reflects the nature of the location and the energy storage mechanism using molten salt. Nevertheless, in terms of total annual output, this is similar to building a 60 MW gas turbine, although the gas turbine would always be limited to 60 MW, whereas the solar facility can output at higher levels through much of the day when businesses are open and drawing on the grid.

By the end of Phase 2, total capacity of the facility will be over 500 MW, at a capital cost of some $5 billion (although The Guardian puts this at $9 billion). Annual generation will amount to some 1500 GWhrs per annum. The per capita consumption of electricity in Morocco is around 1 MWhr, so this represents electricity for 1.5 million people. In the case of the USA, it would offer power to only 130,000 people. Phases 1 and 2 will occupy a land area of some 1900 hectares (about 4.4 by 4.4 kms)

The justification for the project is interesting and can be found in one of the documents on the World Bank project site. Carbon pricing figures strongly although there are no immediate plans for a robust carbon pricing system to be implemented in Morocco. The report concludes that Concentrated Solar is not economic on the basis of conventional cost-benefit analysis (the economic rate of return is negative over the anticipated 25-year horizon of the project); the economic benefits are taken as the avoided costs of the next best thermal alternative, which is CCGT using imported LNG. To be economic at the (real) opportunity cost of capital to the Moroccan government, the valuation of CO2 would need to be US$92/ton of CO2 (calculated as switching value, i.e. NPV of zero), or US$57/ton of CO2 when calculated as the Marginal Abatement Cost (MAC). The justification for the project is largely on the basis of macro-economic benefits for Morocco (jobs, technology transfer etc.) and global learning curve benefits.

The project is situated near a reservoir and is quite water intensive. Phase 1 is water cooled, but this is not the case for the later phases. However, there is ongoing water use for cleaning of the solar reflectors. For Phase 1 alone, the water use during operation represents 0.41% of the average yearly contribution to the Mansour Ed Dahbi Reservoir in the wet years, and 2.57% of the lowest recorded yearly contribution to the reservoir. The estimated total wastewater flow to be discharged to the evaporation ponds (visible in the foreground of the picture) is 425,000 m3/year.

Finally, there is the important aspect of emissions reduction. The Noor I CSP plant is expected to displace 240,000 tonnes a year of CO2 emissions. Based on the generation of 370 GWhrs per annum, this assumes an alternative energy mix of natural gas, some oil generation and a proportion of coal. For natural gas alone with its lower carbon footprint, the displacement could fall well below 200,000 tonnes. But like all such projects, this is displacement of CO2 which may result in a lower eventual accumulation. It is not direct management of CO2 such as offered by carbon capture and storage.

The Moroccan CSP is a fascinating project, but even more so as the numbers are put down on paper. With COP22 taking place in that country in November we are bound to hear more about it.

One million tonnes of CO2

The first week of November sees Shell officially open its first major carbon capture and storage (CCS) facility, the Quest project. It is in Alberta, Canada and will capture and store about one million tonnes of carbon dioxide per annum. Construction commenced back in September 2012 when the Final Investment Decision (FID) was taken and the plant started up and began operating for the first time in September of this year, just three years later. It is one of only a handful of fully integrated carbon capture and storage facilities operating globally. There are now many facilities that capture CO2 but mainly linked to Enhanced Oil Recovery which provides an income source for these projects.  Quest has dedicated CO2 storage, developed in an area some 65 kms from the capture site at a depth of about 2 kms.

Quest Construction

The Quest income source is not based on EOR; it has been able to take advantage of the government implemented carbon price that prevails within Alberta. Although the current carbon pricing mechanism has an effective ceiling of $15 per tonne CO2 which isn’t sufficient for CCS, let alone a first of its kind, it nevertheless provides a valuable incentive income to operate the facility which has been built on the back of two substantial capital grants from the Provincial and Federal governments respectively. A supplementary mechanism also in place in Alberta provide credits related to the carbon price mechanism for the early years of a CCS project, providing additional operating revenue for any new facility.

Canada, as it turns out, has become a global leader in CCS. The Quest facility is the second major project to be started up in Canada is as many years, with the Saskpower Boundary Dam project commencing operations this time last year.

As noted, Quest will capture and store approximately one million tonnes of carbon dioxide per annum. It demonstrates how quickly and efficiently large scale CO2 management can be implemented once the fiscal conditions are in place. Quest, which is relatively small in scale for an industry that is used to managing gas processing and transport in the hundreds of millions to billions of tonnes globally, demonstrates both the need for continued expansion of the CCS industry and the importance of carbon pricing policy to drive it forward. This single facility far surpasses the largest solar PV facilities operating around the world in terms of CO2 management. Take for example the Desert Sunlight Solar Farm in California, currently the fourth largest solar PV power station in the world. According to First Solar, it displaces 300,000 tonnes of CO2 annually, less than a third of that captured and permanently stored by Quest.

A key difference though is the use of the word displace. Alternative energy projects don’t directly manage CO2, they generate energy without CO2 emissions. But, as I have noted in previous postings and in my first book, the release of fossil carbon to the atmosphere is more a function of energy prices and resource availability. This means that even when a project like Desert Sunlight operates, the CO2 it notionally displaces may still be released at some other location or at some other time, depending on long term energy prices and extraction economics. There is no doubt that the CO2 is not being emitted right now in California, but that doesn’t necessarily resolve the problem. Quest, by contrast, directly manages the CO2 from fossil fuel extraction.

The requirement to provide alternative energy (i.e. without CO2 emissions) needs to grow, but we shouldn’t imagine that such action, by itself, will fully resolve the climate issue. That will come through the application of carbon pricing mechanisms by governments, driving the further expansion of both the alternative energy and CCS industries as a result.

A video about the Quest project, made by the constructors, Fluor, is available here.

From sunlight to Jet A1

In a world of near zero anthropogenic emissions of carbon dioxide, there remains the problem of finding a fuel or energy carrier of sufficiently high energy density that it remains practical to fly a modern jet aeroplane. Commercial aviation is heading towards some 1 billion tonnes of carbon dioxide per annum so doing nothing may not be an option.

Although planes will certainly evolve over the course of the century, the rate of change is likely to be slow and particularly so if a step change in technology is involved. In 100 years of civil aviation there have been two such step changes; the first commercial flights in the 1910s and the shift of the jet engine from the military to the commercial world with the development of the Comet and Boeing 707. The 787 Dreamliner is in many respects a world away from the 707, but in terms of the fuel used it is the same plane; that’s 60 years and there is no sign of the next change.

Unlike domestic vehicles where electricity and batteries offer an alternative, planes will probably still need hydrocarbon fuel for all of this century, perhaps longer. Hydrogen is a possibility but the fuel to volume ratio would change such that this could also mean a radical redesign of the whole shape of the plane (below), which might also entail redesign of other infrastructure such as airport terminals, air bridges and so on. Even the development and first deployment of the double decker A380, something of a step change in terms of shape and size, has taken twenty years and cost Airbus many billions.

h2airplane

For aviation, the simplest approach will probably be the development of a process to produce a look-alike hydrocarbon fuel. The most practical way to approach this problem is via an advanced biofuel route and a few processes are available to fill the need, although scale up of these technologies has yet to take place. But what if the biofuel route also proves problematic – say for reasons related to land use change or perhaps public acceptance in a future period of rising food prices? A few research programmes are looking at synthesising the fuel directly from water and carbon dioxide. This is entirely possible from a chemistry perspective, but it requires lots of energy; at least as much energy as the finished fuel gives when it is used and its molecules are returned to water and carbon dioxide.

Audi has been working on such a project and recently announced the production of the first fuel from their pilot plant (160 litres per day). According to their media release;

The Sunfire [Audi’s technology partner] plant requires carbon dioxide, water, and electricity as raw materials. The carbon dioxide is extracted from the ambient air using direct air capture. In a separate process, an electrolysis unit splits water into hydrogen and oxygen. The hydrogen is then reacted with the carbon dioxide in two chemical processes conducted at 220 degrees Celsius and a pressure of 25 bar to produce an energetic liquid, made up of hydrocarbon compounds, which is called Blue Crude. This conversion process is up to 70 percent efficient. The whole process runs on solar power.

Apart from the front end of the facility where carbon dioxide is reacted with hydrogen to produce synthesis gas (carbon monoxide and hydrogen), the rest of the plant should be very similar to the full scale Pearl Gas to Liquids (GTL) facility that Shell operates in Qatar. In that process, natural gas is converted to synthesis gas which is in turn converted to a mix of longer chain hydrocarbons, including jet fuel (contained within the Audi Blue Crude). The Pearl facility produces about 150,000 bbls/day of hydrocarbon product, so perhaps one hundred such facilities would be required to produce enough jet fuel for the world (this would depend on the yield of suitable jet fuel from the process which produces a range of hydrocarbon products that can be put to many uses). Today there are just a handful of gas-to-liquids plants in operation; Pearl and Oryx in Qatar, Bintulu in Malaysia and Mossel Bay in South Africa (and another in South Africa that uses coal as the starting feedstock). The final conversion uses the Fischer Tropsch process, originally developed about a century ago.

Each of these future “blue crude” facilities would also need a formidable solar array to power it. The calorific content of the fuels is about 45 TJ/kt, so that is the absolute minimum amount of energy required for the conversion facility. However, accounting for efficiency of the process and adding in the energy required for air extraction of carbon dioxide and all the other energy needs of a modern industrial facility, a future process might need up to 100 TJ/kt of energy input. The Pearl GTL produces 19 kt of product per day, so the energy demand to make this from water and carbon dioxide would be 1900 TJ per day, or 700,000 TJ per annum. As such,  this requires a nameplate capacity for a solar PV farm of about 60 GW – roughly equal to half the entire installed global solar generating capacity in 2013. A Middle East location such as Qatar receives about 2200 kWh/m² per annum, or 0.00792 TJ/m² and assuming a future solar PV facility that might operate at 35% efficiency (considerably better than commercial facilities today), the solar PV alone would occupy an area of some 250 km² , so perhaps 500 km² or more in total plot area (i.e. 22 kms by 22 kms in size) for the facility.

This is certainly not inconceivable, but it is far larger than any solar PV facilities in operation today; the Topaz solar array in California is on a site 25 square kms in size with a nameplate capacity of 550 MW.  It is currently the largest solar farm in the world and produces about 1.1 million MWh per annum (4000 TJ), but the efficiency (23%) is far lower than my future assumption above. At this production rate, 175 Topaz farms would be required to power a refinery with the hydrocarbon output of Pearl GTL. My assumptions represent a packing density of solar PV some four times better than Topaz (i.e. 100 MW/km² vs 22 MW/km²).

All this means that our net zero emissions world needs to see the construction of some 100 large scale hydrocarbon synthesis plants, together with air extraction facilities, hydrogen and carbon monoxide storage for night time operation of the reactors and huge solar arrays. This could meet all the future aviation needs and would also produce lighter and heavier hydrocarbons for various other applications where electricity is not an option (e.g. chemical feedstock, heavy marine fuels). In 2015 money, the investment would certainly run into the trillions of dollars.

What to make of recent emission trends?

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Recent news from the International Energy Agency (IEA) has shown that the rise in global CO2 emissions from the energy system stalled in 2014. This was unusual on two counts – first that it happened at all and second that it happened in a year not linked with recession or low economic growth as in 1992 and 2009. In fact the global economy expanded by about 3%.

Information is scant at this point, but the IEA have apparently determined this using their Sectoral Approach (below, through to 2014), which has been flattening for a few years relative to their Reference Approach (following chart, ends at 2012). The Reference Approach and the Sectoral Approach often have different results because the Reference Approach is top-down using a country’s energy supply data and has no detailed information on how the individual fuels are used in each sector. One could argue that the Reference Approach is more representative of what the atmosphere sees, in that apart from sequestered carbon dioxide and products such as bitumen, the whole fossil energy supply eventually ends up as atmospheric carbon dioxide. The Reference Approach therefore indicates an upper bound to the Sectoral Approach, because some of the carbon in the fuel is not combusted but will be emitted as fugitive emissions (as leakage or evaporation in the production and/or transformation stage). No information has been provided by the IEA at this point as to the Reference Approach data for 2013 and 2014.

Global Energy System Emissions

Reference vs. Sectoral IEA

Putting to one side this technical difference, the flattening trend does represent a possible shift in global emissions development and it has certainly got many observers excited that this may well be so. If this is the case, what is driving this change and what might the outlook be?

It is clear that many governments are now intervening in domestic energy system development. There are incentives and mandates for renewable energy, enhanced efficiency programmes and some level of carbon pricing in perhaps a quarter of the global energy system, albeit at a fairly low level. More recently in China there has been a strong government reaction to air quality issues, which has given rise to some reduction in coal demand, particularly around major cities. But there is another factor as well and that is price – it is perhaps the overwhelming factor in determining fossil fuel usage and therefore setting the level of emissions. Price drives conservation, efficiency, the use of alternatives and therefore demand. Many of the aforementioned energy policy initiatives have been implemented during the recent decade or so of sharply rising energy prices.

A chart of the oil price (2013 $, as a proxy for energy prices) and global CO2 emissions going back to 1965 illustrates that big price fluctuations do seem to have an impact on emissions. Although emissions have risen throughout the period, sharp energy price excursions have led to emissions dips and plateaus as energy demand is impacted and similarly, price falls have led to resurgence in emissions. This isn’t universally true – certainly from 2004 to 2008 the very strong demand from China in particular was seemingly unaffected by the rising cost of energy, although the end of that period saw a global recession and a very visible dip in demand.

Oil price vs. Emissions

The latter part of 2014 brought with it a sharp reduction in energy prices (2015 is illustrative in the chart at $55 per barrel). With a much lower fossil energy price, demand may rise and the incentive for efficiency and the deployment of alternatives could well be impacted, although there may be some lag before this becomes apparent. The combination of these factors could therefore see emissions take yet another jump, but it is too early to see this in the data. 2015 emissions data might show the first signs of this.

There is of course continued upward pressure on emissions as well, such as the growth in coal use that is now underway in India. Over the three year period to the end of 2014, coal capacity increased from 112 GW to nearly 160 GW. This is the equivalent of some 300 million tonnes of CO2 per annum. By contrast, a five year period from 2002 to 2007 saw only 10 GW of new coal capacity installed in that country. Although India is installing considerable solar capacity, coal fired generation is likely to continue to grow rapidly. One area of emissions growth that is not being immediately challenged by a zero emissions alternative is transport. The automobile, bus, truck and aviation fleets are all expanding rapidly in that country.

The other big uncertainty is China, where local air quality concerns are catalysing some restructuring in their energy system. Certain factories and power plants that are contributing most to the local problems around cities such as Beijing and Shanghai are being shut, but there is still huge development underway across vast swathes of the country.  Some of this is a replacement for the capacity being closed around the cities, with electricity being transported through ultra high voltage grids that now run across the country. Gas is becoming a preferred fuel in metropolitan areas, but some of that gas is being synthetically produced from coal in other regions – a very CO2 intensive process. The scale of this is limited at the moment, but if all the current plans are actually developed this could become a large industry and therefore a further signifacnt source of emissions.

As observers look towards Paris and the expectation of a global deal on climate, the current pause in emissions growth, while comforting, may be a false signal in the morass of energy system data being published. Ongoing diligence will be required.

Getting to net-zero emissions

It is looking increasingly likely, but not a given, that a reference to global net-zero emissions or even a specific goal to achieve net-zero emissions by a certain date (e.g. end of the century) will appear in the climate deal that is expected to emerge from the Paris COP at the end of this year. But like many such goals, it is both open to interpretation and raises questions as to how it might actually be achieved.

The background to this is that the issue itself implies that this outcome is necessary. The IPCC says in its 5th Assessment Report;

Cumulative emissions of CO2 largely determine global mean surface warming by the late 21st century and beyond. Limiting risks across RFCs (Reasons for Concern) would imply a limit for cumulative emissions of CO2. Such a limit would require that global net emissions of CO2 eventually decrease to zero and would constrain annual emissions over the next few decades (Figure SPM.10) (high confidence).

However, the term net-zero needs some sort of definition, although this is currently missing from the UNFCCC text. One online source offers the following;

Net phase out of GHG emissions means that anthropogenic emissions of greenhouse gases to the atmosphere decrease to a level equal to or smaller than anthropogenic removals of greenhouse gases from the atmosphere.

The above effectively means stabilization of the atmospheric concentration of CO2, which also aligns with the ultimate aim of the UNFCCC Convention (stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system). This could still leave room for some level of emissions in that climate models show atmospheric concentration of carbon dioxide will decline if anthropogenic emissions abruptly stopped. In a 450 – 500 ppm stabilization scenario emissions could remain in the range 7-10 billion tonnes CO2 per annum without driving the atmospheric concentration higher. This is far below current levels (35 billion tonnes per annum from the energy system alone), but it isn’t zero. It can be classified as net-zero though, in that the atmospheric concentration isn’t rising.

However, such an outcome, while stabilizing the atmospheric concentration may not be sufficient to prevent dangerous interference with the climate system. In that case an even lower level of emissions may be required, such that atmospheric concentrations do begin to fall and stabilize at a lower concentration.

Another definition of net-zero may simply apply to anthropogenic emissions directly, irrespective of what the concentration in the atmosphere might be doing. In this case, any remaining emissions from anthropogenic sources (and there will be some) would have to be offset with sequestration of carbon dioxide, either via CCS or a permanent forestry solution. In the CCS case, the carbon dioxide would need to come from a bio-source, such as the combustion of biomass in a power station. This is what the IPCC have termed BECCS.

A final step which goes beyond net-zero, is to have an anthropogenic net-negative emissions situation, which is drawing down on the level of carbon dioxide in the atmosphere through some anthropogenic process. This would be necessary to rapidly lower the concentration of carbon dioxide in the case of a significantly elevated level that comes about in the intervening years between now and the point at which the concentration stabilizes. Very large scale deployment of BECCS or an atmospheric capture solution with CCS would be required to achieve this.

Finally, there is the consideration that needs to be given to greenhouse gases other than carbon dioxide. Methane for example, while a potent greenhouse gas, is relatively short lived (a decade) in the atmosphere so will require some thought. Even in a zero energy emissions system, methane from agriculture and cattle will doubtless remain a problem.

Both of the Shell New Lens scenarios end in a  net zero emissions outcome by the end of the century, but this is within the energy system itself and does not encompass the full range of other sources of CO2 emissions and other long lived greenhouse gases. Nevertheless, with extensive deployment of CCS the Mountains scenario heads into negative emissions territory by 2100 and the Oceans scenario soon after that (which means there is potential to offset remaining emissions from very difficult to manage sources). Oceans relies on this approach in a major way to even approach zero in the first instance

Many look to renewable energy as a quick solution to the emissions issue, but the reality is far more complex. While we can imagine a power generation system that is at near zero emissions, made up of nuclear, renewables and fossil fuels with CCS, this is far from a complete solution. Electricity currently represents only 20% of the global final energy mix (see below, click for a larger image: Source IEA).

Global final energy 2012

Solutions will need to be found for a broad range of goods and services that give rise to greenhouse gas emissions, including non-energy sources such as limestone calcination for cement and cattle rearing for dairy and direct consumption. While we can also imagine a significant amount of global light transport migrating to electricity, shipping, heavy transport and aviation will not be so simple. Aviation in particular has no immediate solution other than through a biofuel route although there is some experimentation underway using high intensity solar to provide the energy for synthesis gas manufacture (from carbon dioxide and water), which is then converted to jet fuel via the well-established Fischer–Tropsch process. There are also dozens of industrial processes that rely on furnaces and high temperatures, typically powered by fuels such as natural gas. Metal smelting currently uses coal as the reducing agent, so a carbon based fuel is intrinsic to the process. Solutions will be required for all of these.

Whether we aim for a very low level of emissions, true net-zero anthropogenic emissions or negative emissions is somewhat academic today, given the current level of emissions. All the aforementioned outcomes are going to require a radical re-engineering of the energy system in a relatively short amount of time (< 80 years).

What can really be done by 2050?

The calls for action are becoming louder and bolder as the weeks continue to countdown towards COP21 in Paris. Perhaps none have been as bold as the recent call by The B Team for governments to commit to a global goal of net-zero greenhouse gas emissions by 2050, and to embed this in the agreement to be signed at COP21 in Paris.

The B Team is a high profile group of business and civil society leaders, counting amongst its number Richard Branson (Virgin Group of Companies), Paul Polman (CEO of Unilever) and Arianna Huffington (Huffington Post). The team is not just looking at climate change, but the even larger challenge of doing business in the 21st Century; shifting from Plan A which requires business to focus on profit alone, to Plan B which encompasses a more holistic set of objectives around financial performance, sustainability and business as a force for good to help solve challenging social and environmental goals. It is perhaps the next big step forward in what was originally termed “sustainable development”.

Without wanting to question the broader motives of The B Team, I do challenge their view that the climate issue can be resolved in just 35 years. For some this may sound like a long time, but it is the span of just one career. In fact it is the span of my career in the oil and gas industry from when I started work in Geelong Refinery in Australia in 1980. At least in one industry today, IT, everything has changed in that time, but that is not true elsewhere. In 1980 there were no personal computers in Geelong Refinery; today it probably can’t run without them, although the distillers, crackers and oil movement facilities being run by them have hardly changed and in many instances are precisely the same pieces of equipment that were running in 1980. In almost every other industry, the shift has been gradual, perhaps because of the installed base which of course wasn’t an issue for personal computing and mobile telephony. I suspect that this is true in Mr Polman’s own industry (household products) and it is certainly true in Mr Branson’s. In 1980 I flew on my first trip to London on a 747 and today I am in San Francisco, having arrived here on a 747, albeit a slightly longer, more sophisticated, efficient and larger capacity one than the 1980 model, but still a 747 burning many tons of jet fuel to get here. During his time in office which started with the election in 1980, Ronald Reagan replaced the existing Air Force One 707 with a 747 which still flies today but which Mr Obama has just announced will be replaced with a 747-8. Those planes will likely fly for some 30 years, as will all the other planes being built today, with many just entering the beginning of their production runs (787, A350, A380), rather than heading towards the end as we might be with the 747 series. There are also no serious plans for the jet engine to run on anything other than hydrocarbons for the foreseeable future (i.e. 50+ years) and even the attempts to manufacture bio-hydrocarbon jet fuels are still in their commercial infancy.

So why would we think that everything can be different in just 35 years? There is no doubt that to quickly and decisively solve the climate issue and have a better than even chance of keeping the surface temperature rise below 2°C that we need to do this, but that doesn’t mean we can. To start with, there has to be tremendous political will to do so and to be fair, this is clearly what The B Team is trying to foster by making the call. But political will isn’t enough to turn over the installed industrial capacity that we rely on today, let alone replace it with a set of technologies that in some instances don’t exist. The development and deployment of radical new technologies takes decades, with the energy industry able to make that change at about half the rate of the IT industry. Even the latter has needed nearly 50 years to invent (ARPANET in 1969) and extensively deploy the internet.

We are now seeing real progress in the sale of electric cars, but even there the numbers don’t stack up. To completely outpace conventional vehicle manufacture and replace the entire legacy stock of on-road vehicles will take about 50 years, assuming a ramp up of global electric car production of at least 20% p.a. every year until all internal combustion engine manufacturing is phased out. While this might be conceivable for personal transport, the progress on finding an alternative for heavy transport, including ships, is slow.

For medium to heavy industry that relies almost completely on hydrocarbon fuels for high temperature operations in particular, there are no easy alternatives. Electricity could be an option in some instances, but almost all operations today choose coal or natural gas. For smelting, coal is essential as it provides the carbon to act as a reducing agent for the chemical conversion of the ore into a pure metal.

Perhaps the area in which rapid progress will be seen is electricity generation, where a whole range of zero emission technologies exist. These include wind, solar, geothermal, tidal, nuclear and carbon capture and storage. But even with complete success in this one area, we shouldn’t forget that electricity is less than 20% of the current global final energy mix. This will surely rise, but it is unlikely to reach 100% in 35 years given that it has only moved from 11% to 18% the last 35 years.

Shell’s own New Lens Scenarios show that significant progress can be made between now and 2050, but not in terms of a massive reduction in emissions, although that process is clearly underway in the Mountains Scenario by then (see below). Rather, the time to 2050 is largely filled with the early deployment of a range of new energy technologies, which sets the scene for rapid reductions to net-zero emissions over the period 2050-2100. Another critical development for the near-term is a complete global policy framework for carbon pricing. Even assuming big steps are made between now and Paris in even getting this into the agreement, the time for implementation is a factor that must be recognised. With a fast start in Paris, the earliest possible date is 2020 in that this is when the global agreement kicks in, but even the EU ETS took 8 years between initial design and full operation, similarly the CDM alone took over 10 years to fully institutionalize. Expanding full carbon pricing globally in the same period is challenging to say the least.

NLS Emissions to 2100

The aspiration of the B Team is laudable, but not really practical. The Paris agreement should certainly be geared around an end-goal of net-zero emissions but the realistic, albeit still aggressive, time span for this is 80+ years, not 35 years.

 

A bit of thermodynamics

In conjunction with the ADP meeting in Bonn last week, the UNFCCC held a Technical Expert Meeting (TEM) on Carbon Capture and Storage. It was really good to see this critical technology finally getting some airtime at the UNFCCC and even more importantly the attendance at the meeting by the Parties was good. There was plenty of interest, lots of good questions and a real desire to understand how CCS could be further advanced and more importantly deployed. On a historical note, the meeting was held in what was the German Bundestag between 1949 and 1999. The pigeon holes used by the MPs were still there and dutifully labelled with names such as Dr. A. Merkel.

The morning session covered the technology more broadly and focussed in on some major CCS projects either in operation or under development around the world. I had been invited to speak about the Shell Quest Project in Canada. The afternoon session had a focus on the “U” in a new acronym now entering the discussion, CCUS or Carbon Capture Use and Storage.

Carbon Capture and Use sounds like a great way forward; why not capture the CO2 and put it to good use? That way there will be an economic incentive to tackle emissions and the problem will be solved. This took me back to a dinner at COP19 in Warsaw last year where one participant suggested that CO2 be commoditized such that it would be used even more widely. Unfortunately, this is where thermodynamics gets in the way.

Carbon dioxide sits at the bottom of a deep thermodynamic well.

Thermodynamic well

It is a by-product from a very energetic chemical reaction, the oxidation of a hydrocarbon molecule (i.e. combustion). This releases a tremendous amount of energy (which is why fossil fuels have such value), but leaves us with CO2, which then doesn’t have the energy to react quickly with anything. As such, it is very stable and any chemical use for CO2 which converts it into something else requires a similar amount of energy to that produced when the CO2 was created in the first place. One of the key presentations at the CCS TEM was about the manufacture of polycarbonates (and other chemicals) from CO2. This was an excellent piece of work, but the tricky subject of process energy doesn’t jump out of the presentation.

There is also another tricky subject that needs to be opened up; for the most part, the use of CO2 in chemical processes has no impact on the atmospheric CO2 balance, unless of course the chemical is eventually sequestered. Otherwise the CO2 simply returns to the atmosphere when the chemical is used or the plastic degrades. Even if sequestration is the end point, chemical processes will never operate on the scale necessary to manage global CO2 emissions from energy use.

I did a bit more searching on these subjects and found an excellent paper at the University of Bath online publication store (originating from Imperial college), but beware it is long, detailed and very technical. However, an extract from the early part of the paper highlights the above points:

The development of methods to activate and use CO2 to prepare chemicals and materials is an attractive research goal. Carbon dioxide is abundant, renewable, of low toxicity and is emitted as a waste product from a myriad of industrial processes. A longstanding goal of synthetic chemistry has been to develop catalysts and processes which consume it, however, such reactions pose significant challenges. As the most highly oxidized state of carbon, CO2 is the lowest energy state of all carbon-containing binary neutral species: indeed, CO2 and water are the end-products of most energy releasing processes, including combustion and metabolic pathways. The table below illustrates the free energy of formation of carbon based molecules: the large energy required to reduce it is the most significant obstacle. This energy can either be directly input as physical energy or indirectly via the use of reactive chemical species as reagents; it is the latter strategy which powers the copolymerisation of epoxides and CO2. Free energy of Formation

Nature is successful in transforming approximately 200 billion tonnes/year of CO2 into carbohydrates via photosynthesis. Synthetic chemistry has been less successful, so far there are only a limited range of reactions which can transform CO2 to useful products, those that yield materials with high market volumes and/or economics are even scarcer. Successful reactions include the synthesis of urea (146 Mt/y, 2008), inorganic carbonates (45 Mt/y, 2008, mostly Na2CO3 via the Solvay process), methanol (6 Mt/y), salicylic acid (60 kt/y, 2003, via the Kolbe-Schmitt process), organic carbonates (100 kt/y, 2009; the subject of recent reviews) and polycarbonates (a few kt/y). Current production volumes for aliphatic polycarbonates produced from CO2 are small, however, the polycarbonates sector as a whole is large and growing. In Asia alone the sector is forecast to grow by 8-10%, resulting in the construction of new polycarbonate plants and opportunities for new technologies. Finally, it is important to note that CO2 consumption by chemical processes (approx. worldwide ~ 100 Mt/y) cannot impact global CO2 levels, nor are they a means to address climate change (UK CO2 emissions in 2008 from power stations exceeded 200 Mt/y). However, they could be a means to add value to a portion of the CO2 from carbon sequestration and storage (CSS) processes.

The last point is critical and it is why processes such as described above and the use of CO2 for enhanced oil recovery (EOR) are so important. All of these give real value to a modest amount of CO2. This is nowhere near the scale necessary to impact atmospheric concentrations, but enough to allow carbon dioxide capture plants to be built, which in turn allows capture technology to develop and become more cost competitive. This then makes CCS a more attractive option over the longer term and gives confidence that it is commercially viable at a certain carbon price.