Low-carbon showers fight climate change and save £100s off household bills

Low-carbon showers fight climate change and save £100s off household bills

Climate change

The world’s climate has continued to spin relentlessly out of control irrespective of the terrible impact of the COVID-19 pandemic over the last few months. In the US, the Southwest is locked in the grips of the first human-caused mega-drought, and in the UK, the first half of 2020 has already left reservoirs dry. This year could compete with the five previous – together the five hottest years for the planet on record.


Climate change and water scarcity is a global problem and more than ever we are aware of the need to reduce our impact on the environment. Water is becoming more scarce at the same time as the population and demand for water is increasing. As a result, the need to develop practical and innovative ways to reduce water and energy use and lower greenhouse gas emissions is crucial to safeguard the future of our planet.


Joining up water and energy

According to the Energy Savings Trust, personal washing i.e. showering and bathing, accounts for around 33% of the water used in the home, but it’s not just about the amount of water – it’s also about the amount of energy required to heat the water.


Water consumption in an average household


Hot water demand is the second largest consumer of domestic energy after space heating. Energy for personal washing alone accounts for a staggering 26.6% of the total household energy and is likely to increase due to the push for energy-saving home improvements such as cavity wall and floor insulation.


Energy demand and proportion generated for hot water consumption in an average household


Rising fuel costs

Affordability is a very real issue. Since water services were privatised in 1989 the average household water bill has risen 40% above inflation, peaking in 2014/15. Despite a slight reduction the average water and sewerage bill today is around £397 a year.


The cost of energy has tripled in the last 20 years outstripping all other services. In April 2019 around 15 million households on standard variable tariffs have seen the cost of their electricity and gas soar by 11% and 9% respectively in only a short amount of time – driven by Ofgem’s energy price cap. Today, around 11 million homes are on default and those affected, and using a typical amount of energy, have seen their energy bills rise to around £1,254 a year.


To put this into context, the average UK household spends 5% (£1651) of its total income on water and energy bills. For those living in the poorest areas and communities this percentage is a lot higher and the harsh reality is that around 6.6 million (1 in every 4) households live in fuel poverty.


Carbon emissions

When it comes to personal hygiene showering is generally better for the environment than bathing, however, a shower’s carbon footprint is dependent on a number of circumstances such as duration, flow rate and how the water is heated. When comparing heating fuels in a standard dwelling, gas is the cleanest of the fossil fuels – for each unit of energy of heat, its CO2 emissions are over a third less than electricity from the grid. This is mainly because of the heat wasted at power stations during the process of generating electricity. However, as electricity is generated more and more from renewable sources like wind farms and hydroelectricity, this will become less of a problem.


Annual carbon emissions by shower type


Water companies use a lot of energy to treat water, pump it to and from the home and then treat it before returning it to our rivers. Showers which use less water reduce this impact. Electric showers for example work by only heating the amount of water that is required per shower; the cold water from the mains is pumped through the shower unit where an electric element heats the water very quickly, so there is little wasted hot water compared to heating a large hot water cylinder. The downside is that electric showers have low flow rates (maximum around 5 l/min) compared to 10 l/min for a mixer shower and tend to provide a lackluster experience – particularly in winter when the shower does not get as warm as it does during the rest of the year and flow rate is reduced, meaning any savings in carbon emissions due to lower flow rates may be lost by users having to take longer showers.


Water-efficient showers 

Kelda Technology are the inventors of water-efficient showers that reduce carbon emissions by using less water and energy. They are designed and manufactured in the UK and have been proven to deliver a better shower experience from as low as 5 litres/minute – thanks to their patented ‘air-powered’ technology.


Kelda’s air-powered shower technology is the result of over ten years of development – drawn from cutting-edge aerospace and automotive engineering. It has even received backing from the Department of Energy & Climate Change (now, the Department for Business, Energy and Industrial Strategy) and the Carbon Trust.


Over the last few years their showers have been vigorously tested in the most demanding real-life environments, such as the Queen Elizabeth Olympic Park, to ensure they can withstand the pressures of high usage. In every trial Kelda’s air-powered showers have proven to reduce water consumption, energy costs and carbon emissions and crucially 100% of users have testified that despite using a lot less water the effective spray force from a Kelda shower feels greater than the previously installed shower.


How it works

Conventional ‘aerating’ showers use the Venturi principle to restrict flow and draw atmospheric air into the water through a small hole in the shower head. This aerates the water to change the ‘feel’ of the shower but has no measurable boost in performance. It is completely reliant on the water pressure and in low pressure sites with low flow rates of less than 6 l/min there is almost no aeration – therefore little or no benefit.


Kelda Technology - Eco-Shower - Patented Jet-Type Nozzle


In contrast, Kelda’s patented air-powered showers use the principles of gas turbine fuel injection technology. In simple terms, each shower features an intelligent microprocessor and powerful digital fan which controls the delivery of water and air to the shower head. Within the shower head, air is propelled through an array of jet-type nozzles forming a low resistance air stream. The laminar water is injected into the air where it accelerates and breaks up into the perfect size droplets (larger droplets are better at retaining heat). Thanks to the low resistance air stream each droplet is able to travel further with more momentum to deliver an increased ‘effective spray force’.


Satisfaction from showering is not merely about how much water. It is also about the pressure of the water from the shower head. Kelda call this the ‘effective spray force’ and this is where the Kelda shower is so unique. In a study carried out by the University of Southampton it was found that a Kelda shower provides an effective spray force of c. 200% meaning a Kelda shower at 5 l/min will feel like a mixer shower running at 10 – providing a much better shower experience when compared to an electric shower. And, due to lower water demand it allows for the specification of a smaller hot water cylinder – a key consideration when using heat pumps where 200-litre capacity is now commonplace.



By installing water and energy saving products such as Kelda Technology’s water-efficient showers it is possible to significantly reduce carbon emissions and save money on bills – with the benefit of having a better showering experience.


Kelda Technology - Benefits & Annual Savings



  • Better shower experience – for same flow rates
  • Cheaper to run – save £100s off water and energy bills
  • Help fight climate change – less CO2 emissions
  • Easy maintenance – larger jet-type nozzles are less resistant to limescale blocking
  • Sleek shower panel design – 6mm toughened glass
  • Two shower heads for improved washing and rinsing – flexible shower head with separate handset/hose
  • Reduced risk of scolding – TMV2 thermostatic control
  • Complies with water regulations to ensure the highest water standards and quality
  • Exceeds Building Regulations: Part G
  • Reduced water demand allows a smaller hot water cylinder to be fitted
  • Faster payback than other energy-saving products
  • Proven technology – tested in Health Clubs



¹ Review of domestic water use in Great Britain: At home with water, Energy Saving Trust, July 2013.
² Calculations are based on a family of four, each having a 7.5 minute shower once a day. Water and energy prices are taken as an average across the UK. Savings are based on the average of Thames Water £204.23 and South West Water £370.12, equal to £287.18, July 2020.