Riventa maximises output for Hydro
For a major water supplier in England, Riventa have been monitoring a hydro-turbine to see if its maximum possible electrical output was being maintained.
At a key site, river water is pumped to a break tank at the top of a hill, from where it can either overflow or run down the hill to a large reservoir below - or be directed to a hydro-turbine with the same outfall. Riventa were tasked with monitoring the efficiency of the turbine in question – a fixed speed machine (1016 rpm) that operates without any human intervention. Using inlet guide vanes, its load is controlled via flow rate modulation.
Riventa’s FREEFLOW hardware and software system was installed to show immediately whether a proposed change was effective or not. The system also tracked any savings associated with a change and the financial consequences of it.
Originally rated with a best efficiency of 84 percent, the maximum detected was 82 percent. However, the turbine was found to spend less than 10 percent of its time above 80 percent.
Significant differences in power generated for the same flow rate were also observed. For example, at 925l/s, the power generated varied between 185-260kW, showing an efficiency variation of 58-82 percent - thus demonstrating instances when 40 percent more power was generated for the same flow rate.
Working closely alongside its customer, Riventa looked at how to schedule the turbine for the best return within the operational constraints of the overall water network. In highlighting whether scheduling changes were effective or not, the FREEFLOW system provided real-time tracking of any savings associated with a specific change.
The turbine was found to operate at an annualised average of 73 percent efficiency, but if increased to 80 percent this would translate to at least £11,000 ($15,000) per year savings – based on little or no capital investment.
- This is a good example of how we can help identify opportunities to maximise output from a hydro application – with the same technology that we bring to pump and blower installations to help improve efficiencies, create energy savings and prolong the lifetime of assets, Steve Barrett, Managing Director for Riventa, commented.
Maintenance guarantees the availability and reliability of production facilities and equipment. Slight breakdowns or production stops can plunge a company into irreversible financial losses. By adopting a specific maintenance strategy, a company can improve the safety of its operations, monitor compliance with statutory regulation, and improve the overall equipment efficiency (OEE).
During my 16-year career with the Royal Netherlands Air Force, I learned and experienced that having the right spare parts available or not affects the availability of technical systems. Aircraft stood still at Volkel Air Base due to a shortage of spare parts, while those in Kleine-Brogel in Belgium (68 km south) were in stock. For so-called consumables, I exchanged parts monthly with my Belgian colleagues. As a result, we solved each other's shortages and improved the availability of spare parts and thus the deployability of the aircraft.