Friday, 7 April 2017

Think energy savings - think water savings too.

I have long been concerned about energy and climate change but recently I have been thinking about water too. There are a lot of similarities - in supply limitations, environmental impacts, and the fact that they are essentials for life but (for us in the developed world) extraordinarily cheap. The principles for water saving are the same as for energy too. If you have concerns about energy and climate change you should be thinking about water too.




Water and energy are very similar when you think about it:

Most people don’t notice how much they use.
If I buy a lot of clothes my wardrobe gets full. If I splash out on wine I am reminded the next morning by the bottles in my rubbish bin. But when I use energy or water, it is gone and forgotten except for the reading on the meter. Many people don’t even have a meter for water.

Energy and water are both finite.
At the moment energy does not feel very finite because as long as we are using fossil fuels the only limit is how fast we can get them out of the ground. However if we restrict ourselves to renewable sources then there are quite severe practical limits on what we can extract (which I won’t go into here but see the 2050 calculator and also the excellent book Sustainable Energy: without the hot air by David Mackay). Our water supplies are similarly constrained depending on where we live.

Supplying water and energy damages the environment
When we consume water or energy we are indirectly responsible for the damage to the environment due to supplying it. For energy that includes air and water pollution from mining and from burning fossil fuels or biomass. Wind power and solar are relatively clean but they have a significant impact on the landscape which some people regard as damage. Also there are impacts due to construction.

For water, the environmental impacts depend greatly on where it comes from and are generally mild most of the time – until there is a drought. In Cambridge we get our water from aquifers in the chalk to the South and East. These aquifers also feed various streams that run dry when we extract too much. Some streams that are particularly import and sensitive, such as the Lodes, the River Granta and the River Rhee, are protected by pumping water into them when the groundwater level is low. This requires more water still – one reason why when we have a drought we need more water than before. In areas where water comes from rivers and reservoirs low flows can also have a huge impact.

We have some influence over the environmental impact of our energy use because we can choose our supplier. I get my energy from Ecotricity which is one of a number of ‘green’ energy suppliers (see 'We love Green Energy' for reasons to switch). We don’t have any choice in our water supply except by moving house. However, water companies are required to consult with stakeholders on their water management plans (hence my involvement with the Cambridge Water Company customer panel).

Energy and water are both cheap
Water is cheaper than energy: the average water bill is only £1.06 per day and only 1.4% of the median gross salary. Energy is a bit more: £3.01/day for a dual fuel bill and 3.6% of the median salary. Elsewhere clean water can be very expensive. In parts of Africa people spend a quarter or more of their earnings on water. (see Wateraid.)

Raising prices to manage demand would be regressive
Of course energy and water are both essentials and many people have to watch every penny. Hence using standard market economics to limit demand would be completely unacceptable. If we raise prices enough to discourage well off people from wasting it we will hit some less well off people very hard.

In theory there are ways to get around this – for example using a quota system or a tax that is redistributed, like the carbon fee and dividend (see How is the EU going to meet carbon targets?). Such schemes have been proposed but so far none have been tested.

Waste not want not
In the absence of either of these, how do we encourage people to use less? For my parents generation waste not want not was ingrained into their psyche – at least partly due to the rationing in wartime. As I grow older I tend to feel more the same way.

Here are many ways to reduce the impact of water and energy use

PrincipleEnergy examplesWater examples
Avoid wasteDon’t overfill the kettle
Don’t heat rooms you are not using.
Reduce heat loss from your home with draught stripping and insulation.
Don’t leave the tap running when washing up or brushing your teeth.
Don’t water the garden unnecessarily.
Don’t use a hose to wash the car.
Reduce serviceWear warm clothes and turn down the heating thermostat.
Have a smaller TV.
Take less time in the shower.
Shower instead of taking a bath.
Select drought tolerant plants for the garden.
Increase efficiencyMake sure you have efficient appliances:
Fridges and freezers
Ovens and cookers
Dishwasher and tumble dryer
Heating system
Make sure you have efficient appliances:
Toilet
Shower head
Washing machine
Dishwasher
Use free resources from the environmentDry your clothes on a washing line outside.Use a water butt to collect water for the garden.

For more tips on saving energy see the Transition Cambridge advice pages. For water savings Waterwise has lots of suggestions.


You can recycle water but not energy
Energy cannot be created or destroyed but using it transforms it into less useful forms. For example whenever you use an electrical appliance the energy ultimately turns into heat. This can be a problem in the summer when you are trying to keep your house cool and it isn’t much use in the winter either, considering that you can heat your home more efficiently with a gas boiler or an electric heat pump.

It is easier to recycle water but it takes energy to clean it up. You could use grey water from bath and shower to flush the loo but if it stands for long it will get smelly. The easiest way to stop this is to kill the bugs with a ultraviolet light filter.

Water companies can also recycle water. For example Anglian Water, who treats our sewage abstracts water from various places along the River Ouse and also discharges treated water into it. There are abstraction points downstream of discharges – this water is effectively reused but not exactly recycled. For that it would have to be pumped back upstream and discharged there.

Saving water and energy is an investment in the environment.
Water and energy savings bring money savings too but payback times can be long A 150l water butt with fixings and stand might cost you £70. That volume of water, from a Cambridge tap with a meter, will set you back 35p. But money is not the  only issue. Investing in water or energy savings may or may not be good for the wallet but it is always good for the environment, for us and the next generations.

There are often co-benefits – like a warmer house or healthier plants
Plus savings often bring other benefits. Insulating our house has not only reduced our bills it has also made us more comfortable. Similarly, we have water butts partly to save water but also because soft rain water is better for plants than the hard water we get from our taps.

If you are worried about energy climate change you should be concerned about water too
Water resources are under pressure in many parts of the country due to growing population and climate change bringing more droughts. If you are concerned about energy and climate change you ought to be concerned about water too.


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