The UK National Grid has teamed up with 2OC, a company, which has developed “geo-pressure” technology to utilize the enormous pressure inside the UK gas pipelines, which supply UK homes.
(source: www.cryostar.com)
The first of several planned schemes will see the implementation of small turbines inside the gas network, to produce 20MW of clean energy by 2010 from the natural gas that is delivered at high pressures through the pipes.
The innovative technology will support the National Grid, which owns most of the UK’s gas pipeline, in meeting its targets of sourcing all of its internal energy use from renewable technology. It is estimated that on completion of the eight planned schemes across the UK, the combined renewable energy generation could be as much as 1GW – the equivalent a conventional coal or nuclear power station.
Andrew Mercer from 2OC explains that
“Natural gas is at far too high a pressure when it is drilled from underground reservoirs, so can’t be used safely in homes. It would just blow up your gas cooker.”
Instead, the pressure must be released at hundreds of sites across the supply network known as pressure reduction stations (PRSs). 2OC plans to build mini-power stations across these PRSs, to capture this energy, which is currently lost, to generate clean electricity.
Whilst the technology has in some form been in the spotlight before – the US considered it at some sites in the 80s – the huge associated costs have meant that it did not become more widespread. The British engineers expect to reduce costs by combining the technology with a Combined Heat and Power (CHP) unit at high efficiency.
Mercer has also identified another use for the technology, which he calls “free cold“. Reducing the gas pressure also delivers significant temperature drops, from as much as 10C to -30C, presenting an opportunity as a potential replacement technology in refrigeration and air conditioning units. In addition there have been talks about using this technology for large scale cooling close to letdown stations, such as the EU’s proposed concentrated solar power project across Northern Africa (making the project planned for the blistering heat of the Sahara desert more feasible) and also to supply the huge cooling needs of large computer data centres.
The emergence and implementation of such innovative ideas is well received by environmentalists, particularly in light of the momentum we have built on the climate change agenda in the UK. Despite the technology being in its pilot stages in the UK, if implementation of the technology continues across the 2000+ potential sites in the UK, this would significantly reduce the UK’s dependence on foreign imports of fossil fuels to satisfy it’s ever-increasing energy consumption. Whilst enabling the UK to meet carbon reduction targets (to contribute to the mitigation of climate change) and increasing energy security, it should be noted that the technology uses the high pressure from deliveries of natural gas. If supplies are depleting, do we need to consider other ways of using this technology – assuming fewer deliveries gas? I think we do.
In terms of prices, I would expect that after initial investments to install geo-pressure technology at PRSs, the dual function (additional clean energy) which can be harnessed from deliveries of natural gas should reduce the prices of gas for end users, but whether this might be cancelled out by the increasing gas prices from overseas remains to be seem.
This is really interesting, I wonder how close to commercialisation this is? I’ve not heard of this technology before, and the potential market for cooling too. Thanks Nyla!
Great post. What is the impact of these upstream changes on the consumer end in the UK, do you think? Is it thought that this might have an impact on downstream gas prices–will the increase in efficiency per bcm lower prices or is the investment still quite high despite the use of CHP?
Geo-pressure technology has been implemented in pockets in Europe and North America already. The UK pilot projects are currently underway and the first one is expected to be operational in east London as early as 2010. The technology has also been welcomed by the UK government and BERR has confirmed that it will be recognised in the Renewables Obligation also.
This initiative provides the UK with an opportunity to make emissions reductions to meet national (Climate Change Act 2008) and international (UNFCCC and EU targets). It also supports the decentralised energy model being proposed (by Greenpeace and others) – paving the way for a more decentralised approach to energy districution in the UK.
2OC explains that
“Our [current] highly centralised electricity generation model wastes two thirds of the energy contained in the original fuel source.
Geo-pressure on the other hand operates at about 93% efficiency and – with more than 2000 locations potentially able to generate electricity in this way – could already be described as being a decentralised source of energy with the potential to reduce some of the 9% of electricity currently lost in transmission and distribution over the national grid.”
See amends to the end of the post for a response regarding impact on prices.
This article suggests it is the excess pressure in gas pipelines that will produce 20MW. But in its planning application for the first plant to be built at Beckton, Blue NG Ltd (part of National Grid) described it as “a combined cycle biofuel generation plant” and said it will be burning 56,000 litres of vegetable oil a day. This volume of oil would fuel over 14,000 diesel cars doing 40mpg and 12,000 miles a year.
The energy in rapeseed oil is 37.5 MJoules per litre. If 56,000 litres is burnt every day, the energy consumed per hour is 87,500 Mjoules, which is a power rate of slightly over 24MW. With an efficiency of 70%, the useable power obtained from burning the rapeseed is then 17MW. Most of the energy at the Beckton scheme would therefore appear to be coming from burning rapeseed oil and not from gas pressure reduction
And if rapeseed oil is too expensive – it is already in demand for transport biofuels – there is nothing to stop Blue NG importing cheaper substitutes such as palm oil from Asia, which is a major cause of deforestation and biodiversity loss.
The Government has admitted that there are serious question marks over the sustainability of biofuels for transport use. Use of biofuels for power generation is equally suspect. The Beckton development and National Grid’s planned expansion to many hundreds of similar systems should be re-designed to use just the available ‘geo-pressure’ and not be used as way of getting Government subsidies for burning biofuels in the shape of Renewables Obligations Certificates for ‘clean’ electricity.
Mr Mercer is quoted here as suggesting that the ‘free cold’ from pressure reduction systems could be used to help cool concentrated solar power stations in the Sahara.
An interesting idea, but the ‘amount’ of free cold is tiny compared with the power and heat levels envisaged in the Sahara CSP plan. By 2050, the plan (known as DESERTEC) delivers a network of hundreds of 200MW-plus power plants across N.Africa and the Middle East. It’s unlikely that many of these will be co-located with gas pressure reduction stations. Indeed in Morocco, a prime site for CSP plants, there is little or no natural gas.
Globally, the Desertec strategy seeks to provide 10,000 solar Gigawatts by 2050. In 2050, the world will be well past peak gas, and pressure reduction stations will be making just a small contribution to the world’s energy needs.
Solar is the future.
If only the technology were as good as 20C’s public relations. Energy recovered from pressure reduction is only a small part of the 20MW that will be generated; most of it is generated from CHP driven turbine(s), the heat component is used to warm the gas.
When 2OC say “Our [current] highly centralised electricity generation model wastes two thirds of the energy contained in the original fuel source.”, I am pretty sure that in this ambiguous statement they are referring to the energy used to force the gas down the pipes at the pumping stations on the Scottish coast or wherever the gas has come from. This has nothing to do with the calorific energy of the gas. 2OC: If I have this wrong, do tell us and please put some useful technical information on your web site. Then others would be able whether Greenpeace’s blinkered support for this scheme was justified.
Its interesting to note little mention of any use of biofuels in any of the National Grid’s or 2OC’s press releases (available on their websites). The subject was also picked up by the Guardian in a recent article (http://www.guardian.co.uk/environment/2009/jan/06/gas-energy-pressure) which also failed to mention this.
Thank you for your interesting comments. I would welcome further debate on this topic.
Thanks to the last 2 contributors for important correctives. It appears that BlueNG and 2OC are disingenuously lying in putting out this publicity.
For a collection of the peer-reviewed evidence that all agrofuels are carbon positive – in other words contribute more carbon than they save by displacing fossil fuels – sometimes by as much as 1500 times- as so in no terms are at all sustainable see
http://www.biofuelwatch.org.uk/docs/lca_assessments.pdf
John seems to imply that the end of pipeline pressure is enhanced by a pumping station on the rig or the coast so it is not all geo-pressure.
If BlueNG were serious about using the free cold surely there would have been some mention of it in the planning permission. There is none. If it were fully used then the heat from the CHP would not be needed to warm the decompressing gas
Peak Gas is not far away in the North Sea at which point the geo pressure and the supply will decline very steeply.
Let’s think of ways of designing an energy descent to simply use less energy than eternally looking for reasons not to change.
Duncan Law (from Transition Town Brixton)