See how we minimise water wastage
Window cleaning
Window cleaning has always been associated with the ladder and bucket. These have always been an important method of cleaning windows. In the last 10 years the Water Fed Pole method of cleaning windows has come a long way. Once a costly system to purchase has now become an affordable, standard system for window cleaners to use.
The advantages of using this water fed pole method are that of:-
- Risk is minimised due to user not having to work at height (which cannot be underestimated)
- Reduced fatigue compared to use of ladder
- Increase in speed
- Flexibility of cleaning various types, heights and style of windows
- Cleaning of gutters, fascia’s, cladding and conservatory roofs, to mention a few, which are not always achievable through ladder use alone
- The height which can be cleaned is dramatically increased from 1 story (that of using a ladder) to 6 Story
- Glass attracts less dirt therefore staying cleaner for longer.
- Minimal damage to property (walls, grass, tiles, etc. due to lack of contact with these surfaces)
Obviously a downside would be that of the increase in water required. We recognize the need to reduce water use and wastage. It is not only to our benefit to reduce costs but to help you as water provider to help preserve the little valuable water resource available. Because of this we have introduced this water strategy to show our commitment to working alongside the water authority rather than be irresponsible and continue as normal. Please take into consideration that this is our livelihoods and is something we take very seriously.
We are looking to reduce water usage and use different sources of water (grey water) for use with our work. Unfortunately these are not always available so we are looking for an exemption and an approval to use tap water as a last resort.
As a company we use less water than you may think. We need between 1000-1500 litres of water per week. We achieve this through the methods detailed below. In some cases we may need to use the tap to compensate for long, dry periods. Hopefully with regular rainfall we can collect enough water to not have to use the tap.
Stage 1:- Water at point of use.
To clean glass using a water fed pole requires a source of pure water (water with zero total dissolved solids aka tds). This water is stored in a baffled tank in the users van. Sizes of tank range from 250litres to 1000litres. We use a 400litre tank. The water is pumped from the tank through hoses up to 100m long which are connected to a pole which is extendable. The pole has a brush head on the end which is used to agitate dirt on the glass. The purified water is squirted from the brush head onto the glass. The purified water is used to wash away the dirt that has loosened. The reason for using purified water is that it contains zero dirt therefore it will evaporate leaving no residue. The finished product will be a spotlessly clean window.
Problems:-
To be efficient with the amount of water used when cleaning, the water usage needs to be reduced to when the cleaning of the window is taking place.
It would be not uncommon practice in the window cleaning community for water to be used liberally. Not just at the point of cleaning the window but also from the point of the water flow (how quick the water is coming out of the brush head), how long is taken to clean the glass and how long the water is left running before and after the window is cleaned.
Another aspect to take into consideration is that of water leakages.
The amount of water stored in the window cleaners van is limited. So the window cleaner needs to be as efficient as possible with the amount of water they use. Not only from the point of view of waste, but also from the point of view of maximising work duration which is connected to profit.
Solutions:-
To minimise water waste we have two areas that we have put into effect. That of 1) Fixing leaks when they appear 2) Investing in products which help save water.
1) To fix leaks when they appear means carrying a supply of spare connectors and tools which allow us to make fixes on the spot.
2) Products that help save water include a product easily available on the market known as an Aqua Adapter which allows the user to quickly turn water, while having the pole fully extended in their hands, on and off. This means the user can have the water on only when they are cleaning the glass.
Water usage has also been reduced through the use of “fan Jets” instead of commonly used “pencil jets” (these are types of water patterns when the water exits the brush). The advantage with fan jets is that it produces a higher pressure while maintaining a lower flow rate of water and also covers more area of glass, reducing the time spent cleaning the glass.
To control the flow of water digital pump controllers are used. This means the flow rate can be finely tuned by the user, well regulated and automatically compensates for use at different heights. (E.g. maintaining lower flow rates at lower heights but automatically compensates for the increased pressure needed for use at higher heights)
These methods have been in use for many years and have been thoroughly effective.
Please note that user experience is crucial in knowing how long and how much water it takes to clean a window. Just simply using more or less water does not mean that glass is cleaned to a quality standard. We are a company that prides itself on providing a quality finished product.
Another point to mention is that the traditional bucket and squeegee is still used when appropriate. As much as it is “old fashioned” it is still a viable method when cleaning certain windows.
Key points
- Efficient use of water at point of use
- Remove any leaks as soon as they appear
- Only use water when needed when cleaning windows
- Investment of water saving devices
- Experience in use WFP to provide quality service with minimum water use.
- Use of traditional method when appropriate
Stage 2:- Production of Pure water
Water from any source contains an amount of tds. This means when it evaporates it leaves dirt residue. Pure water contains zero tds. To achieve zero tds various methods are used. Depending from where the water is sourced depends on the methods used. For example here in Kent water tds is usually between 350 – 400tds. This is high. In comparison water from parts of wales can be as low as 60tds. Rain water usually has a tds of no more than 10tds.
The methods that are used in areas of high tds would usually involve that of passing the water through 1) sediment filter 2) carbon filter 3) reverse osmosis (RO) membranes at pressure 4) deionising filter medium. A water softener would also be commonly used before point 1 but mainly for use of prolonging lifespan of RO membranes.
A by-product of using a RO requires that an amount (usually between 40-60%) cannot be purified and is known as waste water as it has such a high tds it has little use.
In areas of low tds the main method would be that of using step 4 which requires only passing the water through a deionising filter medium. This requires no wastage of water.
Therefore sourcing water with a low tds is preferred. It requires less equipment and no water is wasted.
Problems:-
Due to the source of water here in Kent being such a high tds we must use an RO to purify our water. As mentioned this means water is put to waste
Solutions:-
There are various types and brands of RO on the market. We have purchased a 40” RO which is that used in the commercial field. This membrane has a higher efficiency to that compared to cheaper products. To increase efficiency even more we have purchased 2x 40” RO’s that are connected in series. This means that the waste water from the first RO is recycled by the second RO. This still requires an amount of waste water, but less than that of the use of 1 RO alone.
To optimize efficiency in an RO, high pressure is an importance. Tap pressure is usually around 20psi. 80psi is required in an RO. A booster pump is used to create the required optimized pressure. Without this the RO would simply be regarded as useless.
With this method we estimate that waste water is around 30-40%.
To further reduce water in the future we are now investing in containers to store the waste water. We are also investing in also storing as much rain water as possible.
Our aim is that when combining the high tds of waste water (around 700tds) with the low tds of rain water the concentrate of tds will be lessened. The next stage will be then to use this combined water as the source for producing more pure water. Please note that there must still be wastage of water due to how an RO works. Using this method we hope to reduce wastage to around 20%.
The next step that can be taken is that of using an RO-Bak which is a product developed by Ionics Systems. This product is a filter medium. It has been designed to pass waste water through and reduce the tds by an amount that will allow it to be recycled through the RO for longer periods. This will reduce waste water to around an estimated 10%
Please note that these waste water percentages are an estimate but ultimately through these further methods we can reduce water wastage.
Through this it not only saves water now, but also is shows our commitment to water usage in the future.
Key Points
- Use of Efficient RO system
- Booster pump to optimize water pressure
- Store Waste water
- Store Rain water
- Recycle waste water with RO-Bak
- Reduce water waste from 60% to 10%
Conclusion:-
We recognize as a company the importance of water. Our aim is to be as efficient as possible with the water we use. From source to point of use. We hope as a company to rely on drinking water as a source as little as possible. It is a strategy that is beneficial for years to come and we hope that we can set a new standard in the use of the water fed pole. Through this report we hope that you understand our commitment to working with the water authorities in their attempts to reduce water wastage. Any question or criticisms are welcomed.
Hose Pipe Bans
On 5Th April 2012 there was a hose pipe ban that came to most of south east England. Depending what water authority you come under the restrictions are different. Under Veolia Water the Ban is alot more restrictive than other areas. We are under Veolia. They banned the use of Water Fed Poles even for business use. Of course this effected us considerably. We created our water strategy so as to work with Veolia to help them understand our work principles and receive and exemption for our business to carry on as normal.
We recognize that water is a valuable commodity. We are more than willing to do our part to help reduce water usage and wastage. Because of this we have put together a water strategy which we have emailed to Veolia. In short it means we are investing to change our water source to be reliant on rain water.
Veolia contacted ourselves and changed their stance on business use when the hose ban kicked in. The confirmation they emailed me reads as follows
“ I am writing to confirm that when the hosepipe ban is introduced on 5th April, this will not include commercial customers. However, as discussed, depending on the situation it may be necessary to impose further restrictions later in the year, but we will, of course, make customers aware of these at the time.”