Water Versus the Carbon Footprint

The water industry is under pressure, not least the onerous task of reducing its carbon emissions. This will be a big challenge, and huge changes are needed if substantial and effective improvements are to be made, writes Gareth Evans.


As the new decade dawns, the latest challenge facing the water industry will be to maintain and improve water quality while driving forward the process of achieving swingeing emission cuts. Squaring this particular circle was never destined to be easy, but with the surprise downgrade of the 31 January 2010 deadline for the signatories of the Copenhagen Accord to submit their final targets and implementation plans from firm to flexible, the added uncertainty scarcely helps.

The EU had offered a 30% cut, but this was based on comparable efforts from other major players – and for some of them at least, it seems political issues may prove to be intractable obstacles. For example, Australia’s policy has been thrown into turmoil following the defeat of climate legislation in the country’s senate, and Obama’s Climate Bill is also under fire in the US second chamber. After the recent loss of Massachusetts’ seat to the Republicans, the task of forcing it through has become even harder.

With global businesses impotently left watching international interests play seemingly endless games of climate poker, the real questions are where does this leave the water industry, and how can it make progress towards its environmental and economic goals?

Carbon conundrum

"If we’re really serious about cutting carbon, the sector’s got a huge role to play," says industry consultant Bevan Rees, and looking at the numbers, it is clear to see why. In the UK alone, the water industry contributes an annual total of around 5 million tonnes of CO2 – about 1% of the entire country’s greenhouse emissions, according to the Environment Agency (EA) – and currently accounts for 3% of the nation’s total energy demand.

"In the UK alone, the water industry contributes an annual total of around 5 million tonnes of CO2."

To put it another way, writing in Utility Week Trevor Bishop, the EA’s head of water resource management, likened the water cycle’s carbon footprint, admittedly with the inclusion of home water heating, to that of the UK aviation sector.

Changing the status quo will inevitably be something of a challenge. As Dan Green, Wessex Water’s sustainability planning manager recently observed, "our electricity consumption has gone up from 185GWh ten years ago to over 260GWh at present. It’s not going to be easy reversing that trend."

The inadvertent convergence of two drivers in particular looks likely to ensure that the task will be a hard one. The first of these is a burgeoning population. Estimated to grow by perhaps 30% over the next 40 years, it will place pressure on the industry’s ability to supply both the greater numbers and the anticipated heightened per capita demand, as well as treat the additional wastewater generated. With over ten billion litres of sewage already being produced daily in England and Wales, requiring an annual 2,800GWh of energy to treat, the extra flow will have an obvious effect.

Although being designed to improve environmental performance, more stringent regulatory requirements form the second factor likely to predispose a rise in the sector’s energy use. The quality standards set by the likes of the EU Water Framework Directive, as December’s EA report "A Low Carbon Water Industry" points out, will themselves "result in some increase in carbon emissions". It seems a classic case of the proverbial rock and a hard place.

These issues are not unique to the UK. Between cutting carbon, supplying more consumers and improving water quality, the industry as a whole finds itself tasked with achieving a distinctly awkward balancing act.

Technical revolution

Technological innovation may hold some of the answers and one area where this could be of benefit early on is in the quest for greater energy efficiency.

"The idea is simple enough: improved efficiency means lower consumption and, in turn, carbon reduction."

The idea is simple enough: improved efficiency means lower consumption and, in turn, carbon reduction, predicating manufacturers to target a procurement demand increasingly based in cradle-to-grave sustainability and ever-lower embedded energy production values.

In the current business climate, this partnership of better carbon management and lower operational costs is an obvious win-win situation and, moreover, it is something that is unlikely to change any time soon. Nevertheless, despite the advances being made worldwide, there are those who question whether this route alone can achieve the level of emission reductions being demanded.

"Efficiency isn’t the whole answer: it’ll only gain you 10 or 15 per cent at best," says Rees. "Of course, we need to use less energy, and use it better – it’s a good start – but I think we need a bit of a revolution. Let’s start looking at things differently and think about a raft of measures – some new technologies, and maybe a new take on old technologies, too."

Old and new

For the water industry at least, the technology gap between the old and the new has already been bridged in the alternative energy arena, all those years of experience with digester gas having left the sector ideally placed to capitalise on advances in optimised energy harvesting.

For many wastewater treatment plants, the alluring possibility of energy self-sufficiency now beckons – perhaps even to the extent of deriving fuel clean enough for company vehicles or provide an additional revenue stream through off-site export. Interest is growing too in the prospect of diversification into other renewable technologies, following the successes of a number of works around the world that are harnessing the likes of solar, wind and hydro power.

Cutting consumer demand is another approach that has been suggested. The idea is appealing, not least because it helps lower energy use at both ends of the cycle – less cleaned water to supply, and less dirty water to clean – as well as fundamentally helping to conserve resources.

"The demands made of the water industry are big and getting the balance right will be difficult."

However, few believe that doing it will be easy. Unless stakeholders are ready to accept the principle of higher or seasonally variable tariffs, good consumer education will remain the key, but many feel that the "save water" message has already gone about as far as it can.

If so, there may be other ways to achieve at least part of the overall goal. For example, the rising popularity of rainwater harvesting and sustainable drainage systems represent direct approaches to addressing both sides of the treatment energy issue and ultimately, legislation could eventually mandate them for new developments.

Some industry players feel that this trend towards adopting a modern version of low-energy / low-tech traditional solutions could also be successfully extended to the water companies themselves. Low-intensity technologies such as trickling filter beds, facultative ponds and reed beds are evidently not appropriate for everywhere, but where they are, they could, and in some places already do, play their part in cutting overall emissions.

Radical future

The demands being made of the water industry are big and getting the balance right will undoubtedly be difficult. The sector is certainly no stranger to meeting the needs of changing times, and mandating a cut in energy – and thus operating costs – is a conspicuous push against an open door. However, while achieving it willingly may not quite call for a revolution, it will need a step change.

At Aqua Enviro’s one-day conference in 2008, Mouchel director of strategic consulting Martin Hall warned that the industry needed "a lot of radical thinking" to meet the necessary reductions. Given the scale of the challenge, it would seem that those words remain true.