Ecotech Energy Projects

The brief

Ecotech was asked to design, manufacture and install a containerised water purification and water bottling system for the Okavango Delta, Botswana. The brief was to custom design the necessary equipment to purify and sanitize the water from the Delta to the point of bottling in reusable glass bottles. In addition, the system had to generate and operate off its own solar power / battery system. The client wanted to reuse glass bottles to alleviate the pressure on a fragile ecosystem where plastic bottles were becoming an environmental problem.

The treatment and power generation process (housed in 2 x 6-meter containers):

• Pre-treatment of the raw water feeding the entire tented camp was upgraded using a more eco-friendly method of treatment, thereby avoiding the use of any harsh chemicals. Tannins are the major problem with the Delta’s water, so ozone is used at quite a high concentration to initially treat the raw water. This helps to oxidize any organic contaminants and sanitize any bacteria. The next stage is a sand/media filter followed by a granular activated carbon filter. The final stage is an ion-exchange system that specifically helps remove tannins. The only by-product of the system is a small amount of salt in the flush water, which is used to regenerate the tannin removal resin. This treated water is fed directly to the camp’s accommodation units
• This treated water is also fed into the water bottling system, which is housed in a 6-meter sea container. After passing through a 5-micron pre-filter, the water is fed through a fully automated Ultrafiltration plant. The product water is stored in a small tank and ozonated for sanitation before being used to rinse and fill the guests’ glass bottles
• The Ultrafiltration plant is PLC controlled, allowing for automatic rinsing and flushing of the UF modules, thereby making it very operator friendly
• There is a carbonation system to produce sparkling water. The system also produces still water, giving the client both options to present to their guests
• An ozone generator maintains sanitation in the product water storage tanks as well as in the filling lines
• Stainless steel bottle filling tables are designed to the client’s specifications
• A specialised bottle dishwasher is installed to sanitize bottles for reuse. This is fed directly from a solar powered water heating system which easily reaches 65-70 degrees C by midday, thereby using very little power to heat the water
• Containers are both airconditioned and the storage unit for filled bottles stacked in crates has a Coolbot controller installed, allowing the temperature to be adjusted down to 5 or 6degrees if required
• The entire system operates off its own solar power – solar panels on the container roofs produce enough power for daytime bottling operations, and a large battery bank stores power to keep the air conditioners operating at night
• On-site training, equipment manuals, log sheets and scheduled maintenance lists for the operators to maintain high water quality are provided

The benefit to the client:

By designing and manufacturing the above equipment, Ecotech was able to assist the client in providing their high-end accommodation establishment guests with water bottled on site. The client was able to reduce its carbon footprint in the Okavango Delta and reduce the number of plastic bottles being brought into the Delta and then having to be taken out again once used

The brief

Ecotech was asked to design and manufacture a prototype off-grid solar unit that could cure fresh sweet potatoes at 30degC for 24hrs then transfer them to a cold room at 12degC for long storage. Both temperature and humidity had to be controlled and monitored.

The installation:

• A standard 6 m container was divided into 3 sections, hot room, cold room and technical space. 8 x 270W solar panels mounted on the roof. A 12000 BTU inverter drive aircon with special control system is used for cooling with waste heat generated used for the hot room. A DC misting system is installed for humidity control. An 800Ah 24V battery system was used with all Schneider Electric components including; MPPT controllers, inverter charger, battery monitoring, electrical DB’s and remote monitoring via GSM.

The benefit to the client:

This system will allow farmers in remote areas to grow and store more crops for long periods of time without deterioration and wastage

The brief

Ecotech was asked to design, manufacture and install an off-grid solar pumping system for a remote cassava root plantation in Mozambique.

The installation:

• 16 x 180W solar panels mounted on the roof of 6 meter container; 1.5kW 3 phase borehole pump control panel; 1.5kW borehole pump system; water storage tanks on towers; 600 meters of irrigation dripper-line system; stand-alone power back-up system for interior lights and exterior security

The benefit to the client:

This remote cassava root plantation had limited access to reliable water for irrigation. By installing a stand-alone containerised system to pump borehole water during working hours to the surrounding fields, this community was able to have better control over their crop, and therefore their livelihood.

The brief

Ecotech was asked to design, manufacture and install an off grid solar PV system for a remote primary school in the Eastern Cape.

The installation

• 4 x 250W of panels; 40A charge controller; 1000W modified sinewave inverter to run lighting, a TV and a video player; 4 x 150Ah 12V AGM batteries

The benefit to the client

A small rural school that previously had no access to instructional media and television as well as lighting in the classrooms are now running as any normal school in the area.

The brief

Ecotech was asked to design, manufacture and install an off grid solar PV system so that they could avoid having to run a costly generator (both fuel and repairs) on a daily basis for refrigeration, lighting and a TV.

The installation

• 4 x 250W of panels; 40A charge controller; 1500W modified sinewave inverter to run lighting (12 lights installed), TV and video player; 4 x 150Ah 12V AGM batteries

The benefit to the client

The Chief’s house that previously had very high generator monthly costs now has 24/7 lighting, and he and his family are able to use their fridge and TV/HiFi systems.

The brief

Ecotech was asked to design, manufacture and install a 7.5 kW backup system for a large residential property. As the distribution board (DB) was quite old, the new installation was to include the building and wiring of a replacement DB. The client also wanted the option to install solar panels at a later date to reduce Eskom costs.

The installation

• 7.5kW Schneider XW inverter charger unit; 400Ah 48V battery bank; battery monitor
• new distribution board

The benefit to the client

The client’s home now has seamless power change over to inverter supply during load shedding and power outages. All their equipment is also now being protected for spikes and surges.

The brief

Ecotech was asked to design, manufacture and install an off grid system for a small farm. The existing installation and Eskom feed was 25kVA three phase.

The installation

• The house was first optimised by installing a heat pump for the water heating and changing 90% of the lighting to LED’s
• The main and sub DB’s were modified to single phase
• 7kWp array of panels were installed with room for another 2kWp if required
• An 8kW ABB grid tie inverter was used that was AC coupled to an 8kW Victron Quattro inverter charger unit
• 1600Ah 48V battery bank with remote monitor were installed
• The system has an autonomy of two days at normal daily usage

The benefit to the client

The client’s home is running fully off-grid with very minimal changes to their lifestyle. Payback time for this investment at current rates is approx 6-7 years.

The brief

Ecotech was asked to design a grid tied solar system to be installed as a carport for a large office building. The client was very interested in the ‘green’ approach and this was the first stage.

The Design

• The area available was calculated to give an output of approx 30kWp
• Various designs were done of the structure
• The addition of electric car charging posts were included on some of the bays
• Schneider 3 phase grid tie inverters specified

The benefit to the client

Approximately 30% reduction in daytime load costs in the office building. Reduction in carbon footprint. Possibility to upgrade using main roof area. Green image for their clients and staff members working in the building.