The British like rainy weather

To many people, rain is a nuisance that you often have to live with if you choose to spend time in the UK. The UK manufacturing company, however, has decided to think positively and make the most of the raindrops that fall from the sky.Instead of sending the water directly into the sewer, it is being used for flushing toilets in part of the factory and in the newly renovated offices by means of a rainwater system which has been developed by the UK manufacturing company. As a result, the manufacturing company has reduced its consumption of clean water by 15 per cent, corresponding to 300 cubic metres.

Relieving the pressure on the sewer system

Niels Henrik Boldvig, NPI, Quality and Environment Manager, explains that the idea emerged as a result of Belgian customers, in particular, demanding professional Grundfos solutions for rainwater collection as, according to Belgian rules, rainwater near commercial buildings must be collected.

-This is not only a question of reducing the consumption of clean water, but also about relieving the pressure on the sewer system, which would otherwise have to be expanded,Niels Henrik Boldvig explains. He continues:

- When we began focusing on rainwater systems in 2010, we had no Grundfos solutions that could be controlled via Building Management systems, and several of our competitors were able to offer rather advanced solutions. Therefore, we collaborated with the Belgian sales company to develop a system based on a number of existing Grundfos parts, including the new CME pump, and this enabled us to offer a high-tech Grundfos alternative within a short time. The end result was a system that stands out from the competition, among other things by taking up less room in the tight plant room where it is often situated.

Simple construction

The basic construction of the rainwater system is simple. Based on local rainfall and planned consumption you decide where you want to take the water from – most often a roof.

- Here, we are taking the water from a downpipe that collects the water from a roof covering some 2,000 square metres, and the water is led to a three-cubic-metre tank. From the tank, the water is pumped to where it is to be used via a small holding tank, which is also automatically supplied with mains water during dry periods. All sensors, pumps and valves in the system are monitored and controlled via a dedicated Grundfos Rainwater System controller, which is now also marketed externally, Niels Henrik Boldvig explains.

The water consumption in the UK manufacturing company could be reduced even more if the tank for rainwater collection becomes bigger and if new pipes are taken to more toilets. This option is still being considered. So far, the rainwater system has been sold to 200 customers in Belgium and it has also been installed at Frisholt, the Grundfos guest house near Bjerringbro, where the rainwater is used for flushing toilets and watering the garden, and is monitored via Grundfos Remote Monitoring. This system will also be installed in the Hungarian manufacturing company, the Danish sales company and in Mexico. If other companies are inspired to follow the British example, Niels Henrik Boldvig states that the system can be used in all multi-storey mediumsized and large buildings.

Efficiency is being considered

In Group Environment, Health and Safety work is being done to get an overview of where in the world rainwater collection is most suitable.

- The obvious thing is to use the system to save clean water in areas suffering from water shortage. However, areas suffering from too much water due to flooding will benefit from collecting rainwater, as this will prevent an overload of the sewer system and avoid rainwater from being led directly into rivers, lakes or seas, says Helle Nystrup, Senior Engineer.

According to Helle Nystrup, rainwater collection is being considered both when constructing new buildings in the Group and when renovating existing ones. The purpose is both to help meet the Group objective of saving clean water and as a means to comply with the LEED requirements that are used as a benchmark for our success in reducing environmental strain within the Group.