Tuesday 24 December 2013

Calculating Carbon Footprints

Moving home often gives us a chance to take stock and think about all the changes since we first set foot in the old home. Moving websites can offer a similar opportunity for reflection, so as I have just moved the Simple Carbon Calculator (www.carbon-calculator.org.uk) I thought I would reflect on changes in that field.

By way of background, this Carbon Calculator (and there are others, I admit) has its origins as a challenge to myself and to support those in the Energy Efficiency Accreditation Scheme. Back in 2001, the UK's Department of Food and Rural Affairs (Defra) had not long published its first guidance to companies on calculating and reporting carbon dioxide (CO2)emissions. Meanwhile, I had been tinkering with websites, and rather fancied seeing if I could convert their guidance into a simple calculator using a newfangled tool called JavaScript. So I took an open source bit of code and - necessarily - simplified Defra's factors a little to produce a basic calculator that you could enter energy use in normal units (kWh, litres, tonnes or other everyday values) and end up with a CO2 value compliant with Defra's numbers.

Over the years, both Defra and I (quite independently, I must add) have enhanced the tools. But as Defra's has become ever more complex with over 4,000 conversion factors at the last count, I have tried to keep mine...simple. That's not to say that it's not useful; I believe that over 90% of households or companies could use the Simple Carbon Calculator to calculate their footprint within 5 minutes (assuming they had their energy consumption data to hand). And Defra's guidance notes and tables, along with 50 pages of assumptions are always available for the other 10%. (Incidentally the background paper, written by Ricardo-AEA is fascinating for use carbon nerds, but lacks the actual factors deduced from their discussions.)

This leads to a key point: calculating a footprint need not be terribly complicated; it's just a question of (a) having all the right data to hand and (b) knowing which are the right factors to use - and the aim of the Simple Carbon Calculator was to at least partly meet the second bit.

At the start, though, I said I would reflect on the changes to the actual calculation, rather than to website techniques which have rendered my old JavaScript "not modern enough" to stay on the previous host site.

First and foremost, the electricity factors have changed conceptually, twice, over the past12 years. When first created Defra thought it was best to use a marginal factor - ie. the emissions associated with generating an extra unit of electricity. In the UK, this was assumed to be electricity from a combined cycle gas turbine (CCGT) as they could be switched on and off most easily (try doing the same with a nuclear power plant...) However CCGT emissions (which were fixed for several years at 0.43kgCO2/kWh) tend to be lower than average UK emissions (which included older gas stations and coal). So although it might be fine for a company or person at the margin, if you started adding up emissions from everyone calculated on this basis, you severely underestimated total emissions.

Recognising this problem, in the mid-2000s Defra moved to a five year rolling average. This captured longer term trends and wasn't unduly buffeted by abnormal power stations (such as nuclear power stations breaking down, which they seemed to have a distressing tendency to do). However over the past few years this has tended to lead to the opposite error, as coal power plants were mothballed and new zero energy generation - especially from offshore wind - has come on stream.

So, for 2013, we have all moved onto a prior year basis, on the grounds that the generation mix last year is probably the best indicator of what it will be this year. This has meant restating prior years (and miraculously losing emissions for the average user), but is probably the correct answer intellectually, unless someone can develop a 12 month forward weather forecast to estimate future wind energy production! However, we may find the downward trend reversing as US shale gas depressing the demand (and hence global price) for US coal, leading to more imports into Europe for power generation.

As you might expect, emissions for fuels (both gaseous and liquid) have tended to be less variable. However even there we find some trends emerging over the last 12 years. Natural gas, which once came almost wholly from the North Sea, is now increasingly coming in by ship from North Africa as LNG (Liquid Natural Gas) - as much as 20% in recent years. And although the Simple Carbon Calculator is designed for Scope 1/Scope 2 emissions (not full "Well to wheel"), Defra's factors do recognise the much larger carbon footprint of LNG.

Road fuels have also changed. Partly as a result of the EU biofuels directive, both diesel and petrol have a small biofuel component, and this has led to a slight drop in the carbon intensity of the fuel, as carbon from renewable sources is not included. That's not to say that biodiesel or bioethanol have anything like a zero carbon footprint; just that it's a bit lower than the equivalent fossil fuels.

Emissions from aviation are a great concern, as the fastest growing source globally. We have always known that the effects of planes flying at high altitudes was not just as simple as their CO2 emissions, but that there were other effects, such as vapour in contrails that also exacerbated climate change. Well, finally this year Defra has accepted the arguments and included an uplift for "radiative forcing". Of course this means that for a typical middle class household flights are suddenly a much larger component of their carbon footprint...

As the calculator has grown in popularity I have added refinements and extra categories, while keeping to the concept of keeping everything on a single easy to use page. This year's enhancements included a much wider variety of default vehicles for those who know the approximate distances driven, but don't have records of fuel purchased. And, as an antidote to higher flight emissions, I have added Eurostar emissions - although these always seem unnaturally low as they are largely based on purchases of French nuclear electricity, and hurtling across Northern France at 300km/h may not be wholly environmentally benign!

So if this has whetted your appetite to find out your own footprint, I ought to tell you where the calculator has moved to. It's still at www.carbon-calculator.org.uk (and don't forget that hyphen), and may also be returning to its old host if I can negotiate with the new style gurus. Or it may be demolished and replaced with something even better, though perhaps not quite so simple to use.

Tuesday 9 April 2013

Mrs Thatcher and Global Warming

I didn't vote for Mrs Thatcher. This is not just the slogan that launched a million tee-shirts but, in my case, absolutely true, even though I was old enough to vote for her Conservative Party. But this short blog entry, written the day after she died, is neither an attempt to hurl abuse at her nor a recognition that some – but not all – of the things that she did (and which I may have opposed at the time) were probably necessary to move the UK out of its stupor in the 1970s. Instead this will focus on one facet that has gone almost unremarked in the obituaries today: Mrs Thatcher was the first major Western leader to "get" Climate Change.

Trained as a research chemist at Oxford, Mrs Thatcher was proud to undertake a dispassionate analysis of the facts placed before her; this sometimes led her to intellectually appealing but socially divisive (and ultimately foolish) policies. But when presented with the relatively immature findings on the science behind climate change (still then known as global warming) she understood that this was an existential threat – more dangerous for the UK, even, than the European Union!

As far back as September 1988 she said in a speech to the Royal Society:
For generations, we have assumed that the efforts of mankind would leave the fundamental equilibrium of the world's systems and atmosphere stable. But it is possible that with all these enormous changes (population, agricultural, use of fossil fuels) concentrated into such a short period of time, we have unwittingly begun a massive experiment with the system of this planet itself.

This was later emphasised when she told the party conference:
The core of Tory philosophy and for the case for protecting the environment are the same. No generation has a freehold on this earth. All we have is a life tenancy—with a full repairing lease. This Government intends to meet the terms of that lease in full.

And by 1990 she was confident enough to say:
The danger of global warming is as yet unseen, but real enough for us to make changes and sacrifices, so that we do not live at the expense of future generations. … The need for more research should not be an excuse for delaying much needed action now.


This led to an early lead by the UK Government in taking measures to combat climate change and a broadly bipartisan attitude to the subject. Sadly the early lead has gone, and the UK is not doing much better than most of its peers in the move towards a lower carbon economy, and certainly behind that other great nation led by a right of centre female chemist – Germany under Angela Merkel. And many of Mrs Thatcher's successors in the Conservative Party would do well to heed those early words spoken almost 25 years ago – especially the UK's current Prime Minister who should note that her words were supported by action as national and international levels.

Thursday 4 April 2013

No longer Beyond Petroleum?



BP has indicated that it is looking to sell its US wind farms, at a possible loss of over $2 billion.  With this move, BP will once again be focused almost exclusively on petroleum ending the ground-breaking diversification into alternative energy under the leadership of Lord (John) Browne.  The vision of forming a company that provided the energy its customers needed to power their lives, but from a mix of increasingly low carbon sources encapsulated in the "Beyond Petroleum" slogan has long disappeared.  Of course, the strapline hadn't really been used for several years, and was being downplayed even before Lord Browne left the company in 2007.

A BP station with solar panels in Eustis, FL in 2002
Just over a decade ago, around the time of the BP-Amoco merger, BP looked as if it might become the first of the oil majors to diversify away from fossil fuels, and address the need to create a lower carbon economy.  Throughout the 1990s, BP was one of the leaders in solar cells and Amoco – through its Solarex subsidiary – was a large player in the growing US market.  BP exemplified this by adding solar panels to the canopies of many of its Connect filling stations and prominently displaying the amount of carbon-free energy generated.  After the merger with Amoco, in 2000 the company also adopted a new "helios" logo to replace the shield that had been used for over 60 years: this could be seen as signifying solar energy, or crops such as sunflowers.

BP planned to invest $8 billion over 10 years from 2005
So what went wrong and why were the wind farms such a poor investment?  BP's investment in US wind has suffered from two factors outside its control and largely unpredictable. The first is that despite high oil prices, other energy prices have not risen as much as anticipated, most recently due to the discovery of how to extract vast quantities of cheap gas from US shale formations.  This has had a knock-on effect on electricity prices, making renewable energy even less competitive on purely financial grounds.  And though Lord Browne knew that climate change should have led to an effective carbon tax, this has never been introduced into the US, keeping conventional electricity more competitive.  Despite the low prices for renewably generated energy, the cost of new wind turbines has fallen faster than anyone foresaw due to over-capacity among Chinese manufacturers.  This has had a knock-on effect on asset valuations for existing wind farms; it is often cheaper to build a new one than it would be to take on an old one at its depreciated value.  (A similar Chinese effect has affected solar, contributing to BP's exit from that renewable after more than 40 years at the end of 2011.)

BP has a third factor, unique to the company – a need to raise capital to fund the clean up and fines after the Macondo disaster.  Inevitably this has made it focus on non-core assets that can be sold – and wind farms, often held in joint ventures – were an obvious candidate. 

Despite this, BP has not totally abandoned alternative energy.  For the time being it remains a major player in liquid biofuels, especially in the USA where it is still named by Biofuels Digest (alongside Shell, but no other petroleum companies) as one of the 10 leaders in the field.  Of course this is an area much closer to BP's traditional road fuels business, and one where its lower cost of capital than smaller start-ups can still give it a competitive advantage.

But I for one will be sad to see the end of the idea of BP as a truly integrated energy company, investing in new cleaner forms of energy, with the hope that it might in our lifetimes achieve what we all find so hard to do: it might really have moved Beyond Petroleum.

Tuesday 19 March 2013

Where's that gas coming from?

Britain is an island of coal set in a sea of oil and gas

The sentiment above has driven much of the UK's energy policy over the past 40 years, since North Sea gas first started flowing at the end of the 1960s. But no more; Britain became a net importer of energy in 2011 and its conventional gas reserves are drying up alarmingly fast. Data from DECC, the Department of Energy & Climate Change shows that production in 2011 (the last available full year) was 21% lower than in 2010, and that for the first three quarters of 2012 shows a continuing decline. So where is (or should) the gas be coming from?

Oddly, it is largely from the near continent, with over 50% of gas imports from the Norwegian North Sea, and almost 15% from Belgium and the Netherlands (although some of this may ultimately have come from Russia). The balance of around a third is from liquified natural gas (LNG) and, perhaps surprisingly, this has been declining. Energy flows are always difficult to analyse, but it appears that higher demand for gas in Asia has raised prices in Qatar, which in 2010 was the largest single supplier of LNG into the UK, using ships that the one shown here.
ShipSpotting.com
© Knut Helge Schistad

Britain continues to get LNG from North Africa - notwithstanding recent difficulties in Algeria - as the recession in Southern Europe reduces demand there.

In one sense this is to be welcomed; LNG has significantly higher emissions than piped natural gas, largely due to the energy used in the compression of the gas (but also due to some needed for decompression, and the fuel oil used by ships bringing the LNG to the UK from Qatar). But it also shows a risk: when a Norwegian pipeline (Langeled) was recently out of commission due to a power cut, prices spiked and the UK was temporarily suffering a significant shortfall of supply. In the third quarter of 2012 this one pipeline provided 33.6TWh of gas, compared to total national consumption of 65.5TWh. As always, diversity of supply is important for security, especially as Norwegian production has also peaked.

So is shale gas the answer? Almost certainly not in the UK for other environmental considerations, although the development of US shale resources has lowered global gas supplies as they too are importing less LNG. Going back to coal is not an option either, for both CO2 and practical reasons (although it is sad that an underground fire has led to the loss of the UK's largest remaining coal mine). I am afraid that the real answer in the longer term is that we still need to cut demand, through greater energy efficiency, and to support this with other offshore technologies - wind, tide and wave. So finally we may one day be able to say:

Britain is an island of efficiency set in a sea of wind and waves

Sunday 17 February 2013

In praise of Paris's Vélib!

It's all too easy for a blog to sink into negativity, carping at all the things that are wrong, misleading or inexplicable. So, this for entry I'll focus on something good…well, not 100% perfect, but perhaps something from which we could learn.

Capital Bikeshare in Washington DC

Cycle hire schemes are all the range in capital cities. Berlin is installing one, London has its Boris bikes and even Washington DC has a scheme (above). But the granddaddy (or should that be grandpère?) of the all is Paris's Vélib, launched in 2007 and with 1,200 docking stations and some 16,000 cycles, the second highest number in the world (after Hangzhou, apparently). That's around 3 times as many bikes and docking stations as in London, and 15 times the number of bikes in Washington. And last weekend I was lucky enough to be in Paris on a dry day, with a number of destinations to visit, so able to test it for myself.

Firstly, it's user friendly. Arriving at the Vélib station nearest to my budget hotel (which was just outside the famed Boulevard Peripherique orbital motorway) it happily gave me instructions in English and accepted my non-French credit card to give me a 24-hour code, asking me to add my own 4 digit PIN. And the daily hire charge was exactly the same as single ticket on the Metro or for a bus. Once done, it was simply a question of choosing a nearby bike and working out the correct angle to pull it to remove it from the locking device. (OK, I'll admit it, I was 90° out the first time and had to re-key in my details to get a second chance.) Thereafter it was plain sailing (no, plain cycling).

Vélib bikes are rather like Boris bikes: heavy and unlikely to be attract cycle thieves, but quite practicable for a reasonably flat city like Paris. They have a 3-speed gear change which I found a bit too ready to change: I only had to wiggle my wrist to find myself unexpectedly in the wrong gear. And, like many hire bikes, for a regular cyclist the top gear was almost the only one necessary.

Why this paean of praise to Paris? Because the Vélib seems to work better than the London bikes (or those in some other cities that seem to discourage non-native users). The key feature is the density of docking sites – they are typically no more than 300m apart, and most have large numbers of stands. This means that there is nearly always space to return a bike near to your destination (a real problem in London) and in most cases there are bikes available.

Velib cycles by night

Of course Saturday may not be a typical day for the system, and returning late at night to Porte d'Orleans Metro station I found the rack empty – but no problem, as the one round the corner still had seven available cycles. And earlier on I had taken the past available bike at the Parc des Expositions. Conversely, I did also find two full racks (both near the Bastille) but only at locations where I was tempted to swap over my bike to avoid the 50c penalty charge for exceeding 30 minutes' use.


It's not perfect: one bike I took out of the rack without a proper inspection proved to have only one pedal (and so had to be swapped over hurriedly.) I am not sure if on a weekday the distribution of bikes may have been more of an issue, although Paris's layout may help, with few skyscrapers inside the Boulevard Peripherique meaning workplaces are more evenly dispersed across the city than in London, and the high density of Metro lines permitting more Vélib stations to be located at termini.

Then, of course there are French drivers. Even when they can see a Vélib bike on the bike lane (and yes, I was wearing my hy-viz jacket) the concept of indicating if they are planning to turn right in front of the cyclist still seems a bit foreign to them. French drivers are also prone to double parking with their hazard warning lights on, and seem to enjoy pulling off without indicating precisely as a cyclist overtakes them. And there seemed to be a significant minority of drivers (largely, but not exclusively taxis and vans) who regard cycle lanes as convenient short-term parking. In fact some of the cycle lanes seem to have been planned by sadists (well the Marquis de Sade was French), such as one dropping cyclists off on the wrong side of the road (well, the English side) at the entrance to the Place de la Bastille, requiring them to enter in the middle of the roundabout over what were really quite uneven cobblestones.

So I suppose I could summarise by saying that the cycle scheme is great value and well organised (each time I rented a new bike it remembered to tell me what to do in English), but that French drivers need to be more aware of the cycles in their midst. I am a reasonably experienced and confident cyclist, but it needed a degree of faith to keep pedalling on in some situations. But if there's one lesson that we could learn it must be that a successful scheme needs a lot of bikes and a dense network of docking stations to be of use. For despite my reservations, I still hope to use the Vélib next time I'm in Paris.

Tuesday 22 January 2013

Climate Change can be mentioned again!

We, the people, still believe that our obligations as Americans are not just to ourselves, but to all posterity. We will respond to the threat of climate change, knowing that the failure to do so would betray our children and future generations. Some may still deny the overwhelming judgment of science, but none can avoid the devastating impact of raging fires, and crippling drought, and more powerful storms. The path towards sustainable energy sources will be long and sometimes difficult. But America cannot resist this transition; we must lead it. We cannot cede to other nations the technology that will power new jobs and new industries – we must claim its promise. That is how we will maintain our economic vitality and our national treasure – our forests and waterways; our croplands and snowcapped peaks. That is how we will preserve our planet, commanded to our care by God. That's what will lend meaning to the creed our fathers once declared.

Well it probably doesn't need me to tell you that the quote comes from President Obama's second inauguration address, delivered in front of 800,000 people yesterday. Strip away the rhetoric though and two things shine through: a recognition that the effects of climate change are visible and damaging, and a commitment to lead the transition on the path towards sustainable energy sources. This is to be welcomed, although it's not perfect.

Sustainable energy sources are but one half of the solution; arguably managing energy demand is even more important, and can often be achieved quicker and at lower cost. And hidden behind this is often a need for stronger economic signals - of which carbon taxes in one form or another are often most efficient. How refreshing it would have been if President Obama had spoken of being able to revamp America's tax code by not adding taxes to the (not so) broad shoulders of a rising middle class, but instead taxing profligate energy use through a broad carbon tax. But maybe that will come; at least Climate Change is back in the lexicon of the president and I don't have to hide behind the euphemism of "weird weather" when speaking to my US colleagues.

(Oh and as everyone else seems to have been counting words, that's 159 out of 2,137 in the entire address or about 7% devoted to climate change.)