Increase Output of Hydro Power Plants with Automatic Brush Cleaning of Heat Exchangers

When heat exchangers in Hydro power plants are fouled and need to be cleaned, turbines are non-productive which means a substantial loss of income. Eqobrush helps to reduce turbine downtime in Hydropower plants. Through a minimal investment, 5% more productive time can easily be realized.

 As the most common and promising source of renewable energy, hydropower is accounting for 16% of the world’s energy supplies (2019) with a total production of 4.300 TWh. The demand for reliable, clean, and affordable power will continue to drive its growth. It is expected to reduce cumulative greenhouse gas emissions by almost 6 gigatons (which equals the exhaust of 1.2 billion passenger cars yearly) by 2050.

Cooling requirements in Hydro Power plants

The following components in Hydro power generation require cooling: 

  • Hydro Generators

Electricity generation in the hydro-generator that is powered by the turbine releases heat that needs to be removed to be able to keep running at optimum capacity. The generators can be air-cooled or water- cooled. 

  • Bearings
  • Transformers
  • Speed governors
  • Turbine shaft axial seals

Cooling issues in Hydro Power plants

Surface water as a cooling medium leads to fouling issues

The cooling is realized by a closed system that circulates the cooling medium (water or oil) over the components and a heat exchanger where it releases the heat to secondary cooling water. The secondary cooling water is the same surface water that drives the turbines and it causes problems with fouling/scaling of those heat exchangers. As a result of this, the turbines need to be shut down regularly for heat exchangers to be cleaned. The economic impact due to loss of income for each day of turbine downtime is enormous, in addition to the budget that needs to be set aside for the workload of this.

The economic impact of cleaning shutdown

Hydro Power Plant calculation example

Using Eqobrush we have witnessed a reduction in turbine downtime from 10% to less than 5% of the total operating hours, simply because of the elimination of the need for heat exchanger cleaning.

To make this tangible, a 100 MW turbine generates 2.4 GWh of electricity per day and at a reasonable electricity cost of US$ 10 per kWh, this equals an income of US$ 240,000.

Reducing the downtime with 18 days per year (5%), the loss of income that can be avoided with Eqobrush adds up to over US$ 4.3 million annually!

Automatic Tube Brushing System for Hydro Power Plants - the most elegant solution

EQOBRUSH - WATCO Group PTE ltd.

EQOBRUSH systems in Hydro Power applications deliver:

  • Reduced down-time and maintenance cost
  • Increased equipment capacity
  • Increased equipment life (and they eliminate tube pitting)
  • Rapid investment payback
  • One-on-one technical support
  • Installation and continual service support
EqoBrush Automatic Tube Cleaning Brushing System For Heat Exchanger

In automatic tube brushing we use a flow reversal valve to regularly (once every 4 hours) reverse the flow of cooling water over the condenser. This will then propel brushes (that are nestled in catch baskets at the end of each tube) through the tubes to remove any fouling from the tube walls. The fouling does not get the chance to settle in and start scaling and will sediment in the cooling tower basin.

Once the automatic tube brushing system is installed there is no more need to open the condenser for leaning. Reduction of downtime and the costs of maintenance are additional advantages to the output increase.

EQOBRUSH can be used for condensers with a diameter of the water in and outlet pipes of up to 600mm with our compact flow reversing valve. This means that we can fit our standard systems to steam turbine systems with an output of up to 40 MW per unit. This makes it ideal for biomass and smaller geo-thermal power plants. Larger condensers can be accommodated with specially engineered solutions.