TWITTERFrequently Asked Questions
We know that new technology is raising many questions in your minds. Here are the
questions we got asked the most frequently.
System
The minimum wave height varies depending on the system Class. Smaller systems are more responsive and are activated by smaller waves than larger systems. Iceberg Class Units start operating at 1 m (3.2 ft) and production gradually increases until it reaches full capacity with waves about 1.5 m (5 ft) high. Other characteristics such as wave period also affect production.
Oneka wave powered desalination systems are designed with 50-60 micron (finer than a human hair) screens covering the intakes. This feature, along with a very low intake velocity design ensures that sea-life entrainment is greatly minimized.
Oneka wave-powered desalination systems convert 20 – 35% of the seawater they intake into permeate (fresh water) compared to 45-52% for conventional SWRO systems. The remaining concentrated seawater (approximately 30 – 50% more concentrated than seawater) is discharged high in the active water column, where it is rapidly diluted back to ambient seawater salinity (no detectable salinity within 2 meters of the buoy). For more details regarding the brine management of our system, please refer to the benefits of Oneka’s solution.
The buoys are typically placed 0.5 to 2 km (0.3 to 1.2 mi) offshore. At that distance they are only slightly visible to the human eye.
Waves in a given area are relatively predictable depending on the season. Before starting any project, an analysis is carried out in order to validate that the waves are sufficient throughout the year. Appropriate production and proper water storage is selected following this analysis to ensure continuity of supply.
If the produced water is higher than the client’s needs, the water can be diverted back into the ocean.
The hulls of the buoys range from high density polyethylene (HDPE) for IceCube class units to steel, aluminum and composites for Iceberg and Glacier class units. The permeate (product) water pipeline is typically made of high-density polyethylene (HDPE).
Oneka water sale agreements are for 10 – 30 years over which Oneka is 100% responsible for ensuring proper preventive maintenance is carried out throughout the contract to ensure that the equipment produces the same quality and quantity of water at the end of the agreement as did in the beginning.
Water
Seawater reverse osmosis (SWRO) membranes reliably removal microorganisms from water 99.9999% (LOG 6) reduction of bacteria and 99.99% (LOG 4) reduction of viruses.
Oneka continuously monitors each desalination buoy’s salinity, flow and pressure. This information is relayed in real-time where it is tracked by the local operators as well as Oneka’s Operating and Engineering teams.
Well water quality (salinity, pH, hardness, contaminants, color, taste, etc.) varies greatly depending on the hydrogeology from where it is abstracted. SWRO permeate (product water) is reliably consistent the world over. Well water (and most surface waters) generally have higher levels of hardness, higher pH and more contaminants than SWRO permeate.
- For potable water use, SWRO permeate (product water) is generally treated with a residual disinfectant (like chlorine) if it is to be sent through a distribution system (piping). Minerals (calcium) might also be added to improve balance and taste.
- For industrial and/or agricultural use, no treatment to use-specific post treatment might be employed depending on the use.
Security
Each buoy is equipped with passive radar detectors and lighting to comply with international maritime navigation standards. Additionally, the buoys’ locations are registered with regional and international maritime authorities and are located to avoid shipping routes and fishing grounds.
The desalination buoys are equipped with covers and security grating as well as surveillance camera systems. Each unit is also provided with GPS systems for remote monitoring that immediately alert in the event of any unusual events on the units.
Installation
The Oneka team has experience in permitting in the US, Canada, Chile, the Caribbean and in many other parts of the globe. Oneka works alongside our clients throughout the permitting process.
Oneka’s system is modular. It is possible to add units according to use and increasing needs.
The basic system can pump water up to a height of 40-50 m (131-164 ft) at4-5 bars (44-73 psi). Solutions can be implemented if pumping to a higher elevation is required.
The permeate (product) water piping is anchored to the seabed floor. Continuing onto land it is placed underground, either trenched or installed with horizontal drilling.
Maintenance
Oneka and its local partners are responsible for system maintenance. Part of our social mission is to create job opportunities in the communities we serve. Oneka trains and employs local operators, engineers and technicians to operate and maintain the systems.
Maintenance is dependent on water quality and weather conditions. Preventive maintenance is done on a scheduled basis while general maintenance is carried out as needed.
Finance
A Water Supply Agreement can vary between 10 to 30 years depending on the project.
It is dependent on different project parameters and should be addressed on a case by case basis.
- Authorizations / permits for onshore work undertaken on your property
- Modifications or addition of storage and distribution infrastructure (tanks, pipes, canals and tanks on your property)
- Specialized post treatment if required.
Urgent Matters
The other buoys will not be affected since the array constitutes a parallel circuit and the installed redundancy is a strength of the system.
Each buoy is equipped with a data acquisition system and telemetry to relay system performance in real time. Alerts from the monitoring system data dashboard alert the team the instant the system detects abnormal behavior.
Storm Management and other environmental hazards
Oneka is continuously increasing the system’s resistance and testing it in various storm conditions. The Iceberg and Glacier Class Systems are designed to automatically deactivate and enter into safety mode, past a preset load limit. This means that the systems remain moored, but with ample slack and elasticity to remain in place but protected from storm damage. If the system is triggered as such, after the storm, the devices can be reactivated in under an hour.
