The 101 of Total Cost of Ownership in water industry pumping systems
Building new and upgrading existing water treatment plants is a costly business. Because the operating efficiency and performance are to a large degree reliant on pumping systems, it is essential that pumps are given due consideration. Matching the pumps to the planned working life of the plant is essential in order for them to come within the overall budget of the construction and operation of the plant.
Get pump selection wrong, then the only outcome will be unplanned – and undesirable - increases in the operating costs of the plant over its working life.
Pump selection – simple or complicated?
For new pumping installations, it is relatively easy to select a hydraulically optimised pump. As long as the requirements to be met by the pump are known, a highly energy-efficient system can be chosen. However, if a system has been in service for a number of years, it is not all that easy to determine its actual running costs and savings potential. In practice, a detailed analysis of a pump’s operating behaviour often reveals that it is not running at its optimal, energy-efficient operating point. This is where KSB’s knowledge and skills come in to play.
Call in the experts
When it comes to pump selection pump manufacturers, or suppliers, should be capable of providing the owners/operators of the water treatment plant with detailed Total Cost of Ownership (TCO) documentation at the project’s planning stages.
So just what is TCO?
In general terms TCO is not dissimilar to Life Cycle Costs (LCC) and refers to the lifetime cost of owning and operating a piece of equipment. Pump sets are a prime example.
TCO is the performance measurement that sets out to reveal the lifetime costs associated with the pump set both before and after it is purchased.
In other words, it looks at the bigger picture rather than merely concentrating on the purchase price of the pump set. Using this data the plant owner/operator can factor-in the purchase price and long term operating costs of the pump set into the overall project budget with a far greater degree of certainty.
The big three issues to think about
TCO encompasses three major elements, these being:
- initial investment,
- up-time (availability) related costs
- the cost of energy consumed by the pump set.
The initial investment takes into account
- the actual price of the pump set,
- designing the installation,
- setting up the electrical and mechanical infrastructure,
- coupling the pump into the piping system,
- commissioning and eventual
- decommissioning and safe disposal.
Up-time related costs
Up-time related costs include
- operating and maintaining the pump and its motor,
- cleaning and unblocking the pump’s impellers,
- replacing worn and broken parts.
During the pump set’s working life certain components such as mechanical seals, bearings and impellers will show signs of wear. If left unattended, these will compromise the efficiency of the pump and lead to greater operating costs. Also to be taken into account are any future changes to the plant which may require the pump sets to be temporarily removed from service or relocated.
Finally there is the issue of energy consumed, and this has the potential to be the biggest expense in running the pump set. Pumps are an essential element of industrial processes and they often use up more energy than necessary. The reasons for this avoidable power consumption are obvious: pump power ratings are either designed with safety allowances, or are not being adjusted to changed system or process conditions.
It can be seen from this chart that taken together the costs of installation, maintenance and operations can be higher than the initial purchase price. The implication, therefore, is that it makes sense to pay more for the pump at the outset because that will produce savings in other areas.