How can I make energy savings on my washdown systems?
With the cost of electricity increasing, one key area we have identified which is often overlooked are washdown systems. Over the years our pump consultants have toured many manufacturing plants and have noticed washdown systems are often running inefficiently. Below we have set out a few way that energy savings can be made, saving your company thousands of pounds, as well as improving hygiene.
- One area that washdown systems waste energy is that they are controlled via an on/off switch and run at full speed through the return loop when there is none or very little demand on the system.
- Another area where we find washdown systems running inefficiently is that one or more pumps run at a fixed speed regardless of demand.
- The pumps are running at a higher pressure than needed, this not only wastes energy but also causes dirt to atomise and spread bacteria unnecessarily.
- Belt driven pumps, incorrectly specified pumps or inefficient pumps are often found as many old systems have not been updated for years.
If you have any of the above on your site, the way to overcome this can be either by installing variable speed controllers on your pumps with a pressure transducer to monitor the discharge pressure on your system. This will then control the pumps according to demanded, ramping the speed up and down accordingly. This will save between 30-50% energy on your system alone.
The other option is to upgrade the pumps to variable speed multi-stage high pressure pumps for example the Grundfos CRNE pumps, these can produce up to 40 bar pressure. These can be highly efficient with some cases saving up to 65% in energy consumption. This can also reduce the chance of waste atomising, therefore reducing the risk of spreading bacteria.
Upgrading your system with variable speed controls or with new variable speed pumps can massively increase life time of the system as it reduces strain and unneeded wear on it. This can be a win-win situation with the energy savings paying back costs of the upgrade and creating ongoing savings, and also reducing engineer attention.
One of the main reasons for having variable speed controls/pumps is that often the system is designed for several users but they are not all in use at once, therefore varying demand on the system.