All water treatment systems require power for a variety of reasons including pumping, heating, separation, sensors and control systems. The more treatment that is required and the further an untreated water source is from the intended point of use, the higher the power demand. The table below shows the energy requirement for different water treatment systems.
| Water Treatment Technology | Energy requirement (kWh/m3) |
| Local surface water | 0.00-0.30 |
| Local groundwater | 0.15-0.90 |
| Recycled water (tertiary treatment) | 0.25-0.45 |
| Brackish water desalination | 0.40-4.00 |
| Recycled water (membrane treatment) | 0.90-2.50 |
| Seawater desalination | 3.00-4.80 |
The power for water treatment systems can be sourced from fossil fuel sources (e.g. grid connection or generators) or renewable sources (e.g. Solar PV or wind turbines). Solar power makes up 44% of Australia’s renewable energy supply. Additionally, according to the International Energy Association, solar (and wind) power are now the cheapest forms of energy available.
Renewable energy, including solar power, integrates well with technologies used in water treatment. In the case of solar power, there are solar powered Direct Current bore/well pumps are used for pumping groundwater to the surface during daylight hours, solar distillation systems can produce clean water from nearly any source of water and solar PV arrays can produce single phase, dual phase and three phase Alternating Current to power electrical systems such as valves and high-pressure pumps.
When considering if solar power is correct power system for a water treatment system, it is important to consider the complete project lifecycle. It is also important to perform a complete site assessment to determine the most appropriate source of power for a given location. There are a range of advantages and disadvantages that must be weighed up when considering the best source of power.
Advantages of using solar power for water treatment systems
- Off-grid capabilities allow for remote installation
- Lower operating costs compared with fossil fuel powered systems
- Reduced maintenance costs
- Localised power generation (reduced transmission lines)
- High solar irradiation near equator reduces solar array footprint
Disadvantages of using solar power for water treatment systems
- Reduced output during cloudy days
- Higher capital costs compared with fossil fuel powered systems
- Fewer operating hours per day than fossil fuel powered systems
- Water treatment system will have larger hourly capacity to achieve required daily production
- Low solar irradiation further from equator increases solar array footprint
Moerk Water have more than a decade of experience designing and constructing solar powered water treatment systems. Moerk Water’s range of solar powered water treatment systems include seawater desalination systems, groundwater treatment systems, surface water treatment systems and sterilisation systems. Contact Moerk Water today to find out more about solar powered water treatment.
