The 4 Best Ways To Manage Your Cost Of Pumping Water
If you’re in the water business, you certainly need pumps to move it. At 62.4 pounds per cubic foot, moving water from its source to its place of utility takes tremendous energy, and high costs. In most cases, this expenditure is unavoidable. In fact, water pumping is a major contributor to electricity consumption across the world.
A POLIS water project reported that in Ontario, the energy required for water-related services like pumping, treating and heating, and steam generation are estimated to be 976 petajoules per year or 271,600,000 MWh/yr. This large amount of energy is enough to heat every home in Canada. In fact, the energy required to pump and treat Ontario’s water (20 PJ/yr) alone is enough to light up every home in the area.
Another statistic says that the energy used to power pumps in water treatment plants and to operate hot water heaters and boilers amounts to 12% of Ontario’s total electricity consumption and 40% of its natural gas demand. << 1 >>
These studies, among others, show that there are several opportunities to manage pumping and operating costs through electricity savings. Large and small operators can benefit tremendously from reducing the cost of pumping water. Unfortunately, there’s no magic formula to bring the costs down!
Industries of all sizes, as well as regular households, can however look into these strategies we detail to improve efficiency and reduce cost.
1. Use the right type of pump for the job
Average pump efficiency is below 50%, and about 15% of pumps are less than 15% efficient. << 2 >> Optimizing a pumping system for any application is a key factor to enhance efficiency. Using pumps and motors that are either too powerful for the job or not powerful enough results in energy waste. It is best to consult a contractor/engineer before purchasing pumps and motors so that the most efficient machine is selected to fulfil the specific needs of an application, in terms of size, power output and drive type.
2. Control the water pressure and flow rate in your system
Reduced water pressure directly translates to energy wasted, which in turn increases the cost of pumping. Several measures can be taken to maintain optimum water pressure in the system. Installing pipes of the right length, diameter (pipe-size optimization) and type can help to maintain hydraulic pressure. Choosing the right pipe is also important because the inside of a pipe (texture-rough/smooth) that comes in contact with the water should facilitate optimum flow.
If the water pressure at the source is low, just installing the right pipes will not help. Water flow control valves (also, throttling valves or bypass loops) can help maintain optimum pressure in these situations. By controlling the pressure and flow rate, control valves can reduce the load on pumps and motors, and thus reduce operational and maintenance costs.
Installing variable speed drives (VSDs) or adjustable speed drives (ASDs) can also help save electricity. Unlike control valves, VSDs manage water flow rates by increasing or decreasing the speed of a motor or pump. This flexibility allows for the adjustment of the flow and pressure of water to suit the requirement without wasting energy, thus enabling maximum efficiency extraction from the system.
3. Use multiple pumps or motors and optimize their usage
Running multiple pumps in parallel is a great option to reduce the burden on a system and conserve energy, especially when water has to be pumped up an incline or from a lower elevation to a higher one. All the pumps in the parallel system only need to operate simultaneously when necessary. A multiple pump system can act as a cost-effective alternative to VSDs and ASDs in many cases.
4. Maintain and monitor water pumping systems
System maintenance, while obvious, is a core part of your operations. There’s no water pump in the world that you can simply install and forget about. A water pumping system will operate at its most efficient level when it’s looked after periodically and is regularly monitored (essential for large and complex systems).
Through checks and maintenance, operators can stay ahead of wear and tear of mechanical and non-mechanical parts such as impellers, seals and bearings. Preventive maintenance ensures that pumps and motors are never without lubrication, and any potentially faulty part is replaced in time. Investing in maintenance always pays off in the long run!