Archive for June, 2008

Question: are patio heaters evil?

Thursday the 26th of June 2008

Qu: I’ve heard that patio heaters are worse than trans-Atlantic flight for carbon emissions. Can this be true?

patio heaterHmmm… I’ve heard this one before, it’s the kind of gloomy end-of-the-world rumour that people like to pontificate as they light up outside the pub under one of the offending appliances!

Patio heaters are obviously so wasteful, in that their job is essentially to heat the open air (!), that they are often held up as an example of societies improvident tendencies. It’s true; they are a complete waste of energy, but as a nation we have many much more wasteful habits which we choose to overlook so a bit of perspective is needed to answer the question.

The average UK patio heater has a consumption of 8.9 kilowatts (kw). That’s quite a lot for a ‘non-essential appliance’. In fact a patio heater turned on for an hour uses enough power to boil a kettle from cold 80 times. And 8.9kw is the average, but most of the, the ones smokers huddle under in pub gardens, emit 12kw or more - there are plenty of 15kw patio heaters out there.

They use bottled LPG (propane) for fuel and for every hour of use a 12kw heater emits 2.6Kg of CO2. (source)

So, how does that compare to the CO2 from a transatlantic flight? Well there’s quite a lot of variance depending on the carbon calculator you choose to use as the assumptions behind them differ - which isn’t very reassuring! For the sake of this question I’ve taken a middle of the road figure provided by CO2balance. This company quotes a distance of approx. 5586 km (return from London Heathrow to New York) and CO2 emissions of 2.54 tCO2 for one passenger.

Your flight would take approximately 7 hours, during which you would produce approx. 2540 kg CO2. Running your 12kw patio heater for the same amount of time will produce 18.2kg. So if you use time as a comparison your flight is much worse.

The answer really depends on your patio heater usage and how many flights you take. The Market Transformation Programme (MTP) who supply government stats report state that use of patio heaters by individuals is relatively low. It’s pubs and restaurants that make the most impact and with the smoking ban increasing the demand for cosy outdoor things are set to get worse.

Before the introduction of the smoking ban, MTP estimated 2006 emissions from heaters at 20.3 ktCO2. They’ve predicted that in the wake of the ban emissions could be between 141 and 282 ktCO2 annually. (yes, that’s KILO TONS). (source)

However before you go vigilante and start persecuting all those pubs trying to heat the world, it’s worth looking at the wider picture. The UK’s total production of CO2 in 2006, according to DEFRA, was 556.5 million tonnes, meaning that the patio heater’s share is negligible, even at the upper end of the MTP’s estimates. Passenger cars, on the other hand, accounted for a chunky 68.7 million tonnes and air travel is increasing every year - and being actively encouraged with the opening of the new Heathrow terminal.

My advice is to boycott the pubs that use the offending appliances (put a jumper if you want to be warm while you smoke), then start finding holiday destinations you can drive to - or even better, reach by train.

Bethan

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Question: Oil use per capita?

Tuesday the 3rd of June 2008
Qu: How much oil do the Chinese use per capita? How does this compare with USA and Europe? What is their projected increase oil use in the next decade?
 
Thanks for this – very relevant to the question that gives the blog it’s name. Before jumping straight to the answer it’s important to recognise that there are two different metrics for measuring a country’s oil consumption: by population or by the total consumed. The chosen metric is important in the global debate over oil consumption and it’s worth looking at both to get a better picture. 
 
Per capita energy consumption (Barrel/person/year)  
United States - 68.81
United Kingdom - 30.18
European Union - 29.7
World -  12.55
China -  4.96
 
Total oil consumption (10/3/barrel/day)
United States -  20,588
China - 7,274
United Kingdom - 1,816                  (Statistics from the EIA) 
 
In light of these statistics it’s easy to see why nations with large populations, such as China, tend to promote the use of population-based metrics, while nations with large economies such as the United States would tend to promote the total consumption metric. Compared to the rest of the world, China’s oil use per capita is still relatively low – especially when you look at the US’s whopping 68.81 barrels per person per year. But when you look at their consumption per year it is relatively high (second in line to the US in a study of 15 nations).
 
What about the projected increase? To get some perspective it’s useful to look at past growth in demand before looking to the future. The increase in Chinese oil consumption is mostly seen as a recent development, supposedly driven by the industrial development of China. In reality, the growth in Chinese oil consumption has been the same in the past two decades. Between 1990 and 1999 annual oil consumption growth in China was 6% on average. Between 2000 and 2006 the average annual oil consumption growth in China was 7%. Also the 2004 anomaly of 13% growth in a single year is nothing new. In 1993 Chinese oil consumption growth reached 10%.
oil use per captia
Figure 1 - Chinese oil consumption and production, source: EIA
 
Between 1990 and 1999, absolute growth was around 2 million barrels per day (mb/d), from 2.3 mb/d in 1990 to 4.4 mb/d in 1999. In the past seven years, absolute growth has been 3 mb/d per day according to preliminary figures, from 4.4 mb/d in 1999 to 7.36mb/d in 2006. If this present trend continues, the demand for oil (and other liquid fuels) in China will grow to 9.2 mb/d in 2010 and 12.4 mb/d in 2015.
oil growth
Figure 2 - Growth trend in Chinese oil consumption
 
Worryingly China’s own oil production increasingly falls short of the country’s needs. The global production of oil has been stable for a few years and will shortly be falling. This could result in conflict between nations for what remains, rising prices and economic recession or worse. It will also increase the incentive to use coal, which could be catastrophic for the climate. Predictions about China’s projected use of oil in the next decade therefore are subject to so many unknowns that they have an air of fantasy.
 
Bethan
 

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