Demand Management series by Dr Ronnie McKenzie – Part 4 of 4: 21st Century Best Practices

Can you share the 21st century best practices you apply for good utility management?

We are using an enhanced version of a normal PRV where you apply additional pressure management during off peak periods, dropping the pressure from the PRV down at certain times of the day. It gives you greater pressure control flexibility. For example, pressures typically increase at night when people are not using water. Using some form of advance pressure control (there are many different forms available), you can cut out that increase in pressure (which is typically what bursts most water pipes) between say 2 and 4 o’clock in the morning when people are asleep. So, I would say that there have been some great advances in pressure management. There are several different pieces of equipment that claim to make huge savings. Again, it’s “horses for courses” and every additional complexity you add to a piece of equipment is simply another link in the chain that can break. You shouldn’t become overcomplicated, but you can add a bit of complexity to it if you feel it can create additional savings and it is cost effective.

These advanced PRVs – are there several manufacturers that make them now?

Every major PRV manufacturer has its own form of advance pressure control, whether it’s electronics or hydraulic. We have tested a number of them, and we have found some that we like to use; but everyone has their own view on this.  We will always recommend using high quality PRVs and high quality pressure controllers which should last at least 50 and 10 years respectively.

Any of the big guys that make good quality valves and have been in the market for 50 or 100 years will have a good product. If you go for a good quality, the valve will give you over 50 years of service. If you go for a cheap valve, then it may only last a few years before giving problems.  A water utility should try to look at the life-time cost of such products and not simply the initial basic purchase cost.