The Princess Alexandra Hospital, Harlow

The Princess Alexandra Hospital NHS Trust

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Following a successful trial earlier this year, the Princess Alexandra Hospital NHS Trust in Harlow has chosen to refurbish all of its public toilets using the Propelair WC system. In addition to the obvious water savings and reduction in utility bills, the technology brings substantial hygiene benefits that are of particular importance in a healthcare setting. Propelair’s flush efficiency has also added value by eliminating blockages in areas of extreme high usage where issues had previously arisen on a daily basis.


The new toilets are expected to save almost 2 million litres of water per year. This will result in a substantial reduction in carbon footprint, as the energy saved by reducing the amount of water that needs to be supplied and treated will reduce annual emissions of CO2 equivalents by around 2,023 kg (DEFRA conversion factors for greenhouse gas reporting 2016). This is the same amount produced by 66 car journeys from London to Leicester!


Propelair is an economically viable solution for organisations wishing to reduce their water consumption and carbon footprint at a relatively low cost. Collectively the Propelair units installed at the Princess Alexandra Hospital NHS Trust are expected to pay for themselves in just 1.9 years via the water savings and associated reduction in bills.


Propelair provides washroom users with a number of hygiene benefits. Every time a conventional toilet is flushed particles of contaminated water become airborne, landing on washroom surfaces. Propelair’s unique displaced air technology efficiently removes all waste with one flush, reducing the spread of germs by 95% and removing over 99.9% of waterborne contaminants (ensuring less risk of cross-contamination during subsequent flushes). This helps to maintain the highest standards of hygiene for staff, patients and visitors at the hospital.

Metered Water Charge Flushes Per Day Current Flush Volume Annual Savings Payback
Water Financial
£3.13/m3 55 8 litres 130,488 litres £408.43 1.9 years

Added Value

The installation of Propelair toilets in several public areas during the trial has resolved a number of issues with blockages.

“We were experiencing blockages nearly every day in one public toilet located outside maternity which was very heavily used. Since replacing this with a Propelair unit 10 months ago there have been no reported blockages. The women’s staff toilet used to block on a daily basis too, but this hasn’t happened since installing Propelair 4 months ago. The toilets work really well and offer savings not just on water but on maintenance costs and call-outs too.”

Bill Dickson (Energy & Environment Manager, Estates & Facilities Department)

Domestic staff at the hospital have found the new toilets much easier to clean than the previous ones, and user feedback has been overwhelmingly positive.

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