New research shows that Southern Water’s pioneering metering programme has had a significant impact on water consumption – a 16.5% reduction compared with the national average of 10%.
The findings are revealed in a study published this month by Dr Carmine Ornaghi and Dr Mirco Tonin who are economists at the University of Southampton and are both Associate Professors. They conclude that the five-year metering programme, which began in 2010 and is now nearing completion, has had a significant effect on water consumption.
With nearly 500,000 meters installed, customers are using, on average, 60 litres per household per day less water. This represents a 16.5 per cent reduction – far more than the national average of ten per cent. When the metering programme ends, this will equate to a regional saving of 30 million litres of water every day across Kent, Sussex and Hampshire - enough to meet the daily water needs of towns the size of Hastings and Worthing combined.
The reduction in demand has also had an impact on customers’ bills. To date, 62 per cent of metered households are saving, on average, £162 a year.
Household behaviour changes immediately on installation
Dr Mirco Tonin, said:
“In our study we find a strong decrease in consumption due to the Universal Metering Programme. What is remarkable is that households start changing their behaviour as soon as the meter is installed, even though they do not immediately have financial incentives to do so, due to the three month ‘grace period’ between installation and switch of contract. This could well be because households take into account that it takes time to change consumption habits, or because the installation focuses their attention on water consumption.”
The economists examined the consumption habits of more than 200,000 Universal Metering Programme customers over a period of four years from 2010. The researchers found that in total customers were making water savings of more than one and a half times the predicted ten per cent.
The research also shows that people cut down their consumption very early in the switching process, even though the metered charges aren’t activated until after three months. In the second month after the installation of a meter, consumers saved an average of 37 litres per day. In the third month, they saved an average of 50 litres per day. The reductions continued after metered charges kicked in, albeit at a slower pace, reaching an average saving of almost 70 litres after the fourth bill – or two years of metering.
The researchers examined four different stages of switching to a metered programme: meter installation and switch of contract; the first three months after switch of contract; the first bill after switching; and subsequent bills every six months. By comparing data with households not in the UMP programme, they were able to compensate for seasonal differences in water consumption, geographic variations and economic conditions.
The results will be updated as new data become available and the Southampton researchers will continue their work by exploring the motivations behind consumers’ water saving actions in more depth.
Southern Water’s Chief Customer Officer, Susan Stockwell, said
“We’re delighted with the results of this independent research which has studied water usage across a huge sample of 250,000 customers. It confirms that the majority of customers are acting on the advice offered by our water efficiency programme, changing their behaviour and reducing their bills. Energy bills are also affected because heating water makes up around 30 per cent of the average household’s energy bill.
“I’d like to thank customers for working with us to save the region millions of litres of water every day which will help to ensure continuity of supply in the densely populated South East.”
Click here to download the study