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CTS was approached by the Botswana Meteorological Department and the University of Hamburg with the request to install automatic weather stations across Botswana. A total of 10 stations were engineered and build at our workshop in Windhoek prior to installation commencement. With our own tower design, the installation time is reduced to nearly 8 hours per tower.

The stations are equipped with sensors from Vaisala, Kipp and Zonen. At the heart of each station is the CR1000 logger from Campbell Scientific. Each station is capable to measure the following:

• Wind speed
• Wind direction
• Humidity
• Air Temperature
• Irradiance
• Barometric pressure
• Ground Temperature
• Rain
• Leaf wetness

In addition to the above parameters the following parameters are calculated by the logger by means of mathematical models.

• Dew point temperature
• Wet bulb temperature
• Sunshine duration

The data from the station is transmitted to ftp servers situated in Gaborone/Botswana as well as Hamburg/Germany on an hourly bases over locally available GSM network providers. Once the data is uploaded to the server in Hamburg, it is processed and posted on a publicly available website. This website collects data of numerous stations across Namibia, Botswana, Zambia, Angola and South Africa for research purposes. A total of 8000km was covered in just under 4 weeks.

Central Technical Supplies (Pty) Ltd. – Geiger Engineering (CTS) was approached by Farmers Meat Market Mariental to design, supply and install a solar water heating system with the aim to reduce the monthly diesel consumption as two diesel boilers are operated to heat water up to 82 deg. C for production purposes.

The water requirements of the abattoir are as follows:

1. 2,000 liter/hour @ 45 C°
2. 3,000 liter/hour @ 60 C°
3. 500 liter/hour @ 82 C°

This adds up to a total daily water requirement at 60 deg. C of roughly 25,000 liter.

The system is design such as to preheat water from 18 deg. C to between 50 deg. C and 60 deg. C before supplying the diesel boiler system, thus reducing runtime and diesel consumption of the diesel boilers. A 20,000L stainless steel tank (non pressure tank) manufactured locally according to CTS design, acts as the buffer tank for the daily water requirement. A total of 120 flat plate collectors supplied by Solsquare Namibia with a total surface area of 300 m2 are connected by means of a 450kW Alfa Laval flat plate heat exchanger to the water tank.

A set of two Calpeda circulation pumps connected to Danfoss variable speed drives and a timer circuit guarantees at all times that the heat from the collectors is effectively transported to the water tank. Flow as well as temperature monitoring on all four ports of the heat exchanger make it possible to determine the instantaneous as well as accumulated kWh produced from the collector field.

Furthermore additional heating energy is obtained from the ammonia refrigeration plant. A heat exchanger is installed on the ammonia discharge side before the existing cooling towers to be able to heat the water during night time as well, as this is the time when the refrigeration plant runs at full capacity to cool down the newly slaughtered meat in the cold rooms. Again flow control and temperature monitoring on the hot water side of the heat exchanger accurately indicate heating energy obtained from the refrigeration plant.
A total of four pump sets have been installed and pumps are cycled on a 24 hour basis in automatic mode. Should at any given time a pump fail, the system can be switched to manual mode to be able to repair the pump without system down time and a resulting increase in diesel consumption.

All systems components are sized such as to allow for future heating capacity upgrades should it be required.

After a year of operation, the plant is performing better than expected and the client is able to safe nearly N$ 60,000 per month on diesel costs, bringing the payback period of the entire system down to below two years. This clearly shows that solar energy, be it for heating or for electricity production, surely is the way forward for a cleaner and greener future for generations to come. CTS is proud to be part of making Namibia and the world a better place for our grandchildren to live in.

National Botanical Research institute approached CTS to upgrade two of their existing AWS to satellite communication and subsequent installation at Kanovlei in the Tsumkwe Area as well as Koichab Pan close to Lüderitz.

Communication is via Meteosat satellites and based on a “fire and forget” principal which unfortunately does not allow remote maintenance procedures.

The stations form part of the SASSCAL Weathernet and measure all important meteorological parameters.

Weather data can be viewed at: www.sasscalweathernet.org 

CTS has electrified two schools in remote northern Namibia funded by the Hanns Seidel Foundation with the aim to provide electricity for lighting, thus extending learning hours for learners well into the night. Both systems are based on BlueNova 4kWh lithium ion batteries, Victron Energy charge regulators and inverter technology. Remote monitoring is possible via the integrated Colour Control GX from Victron. Special attention has been given to the system configuration to prevent total battery shutdown. This is achieved by switching the inverter off at a predefined battery state of charge (typically 20%) and only reactivate the inverter once the batteries are charged beyond a predetermined threshold.

The systems where officially inaugurated by the Ambassador of Germany in June 2018.

CTS was awarded the tender to install a water heating system for the Hilton Hotel Windhoek.

The system was installed according to the following specifications:

•    2x 250kW gas fired hot water boiler

•    2x 6800 liter hot water storage tank (also known as calorifier)

•    1x Danfoss Aqua drive 11kW for glycol circulation pump control

•    2x Automatic bypass valves to control water temperature inside tank

•    4x Hot water circulation pumps

The boilers as well as glycol circulation pumps and one hot water storage tank were installed in the boiler room located in the upper basement of the hotel. The second hot water storage tank is installed on the 9th floor of the Hilton Hotel. A glycol circulation system connects the two calorifier with the two gas fired hot water boilers. The glycol circulation pumps are controlled from one Danfoss Aqua drive with cascading functionality to control the pumping speed depending on the temperature in the glycol line.

Each hot water boiler is cycled on a 24 hour basis, should the glycol temperature fall below a predetermined threshold for certain period of time the second boiler will start automatically.

Automatic bypass valves guarantee that the water temperature of each calorifier is kept at a constant 60 – 65 degrees Celsius.

O&L Leisure is well known for their high-quality lodges and hotels. Guests all over the world expect the best standards, which start with flawless bed and table linen and toweling with a soft handle. Carefully selected and exquisitely finished laundry is good advertising for hotel standards. And, at the same time, laundry care is a significant investment. It is therefore all the more important that hotel laundry is long-lasting and durable, underlining care and attention to perfection.

CTS designed and installed the full turn key solution for Strand Hotel, which included Miele washers, tumblers and drying ironers, as well as various accessories, including a form finisher. Miele professional machines are custom-made to meet the individual needs, and they offer the perfect solution with optimum economy.

Strand Hotel can now pride themselves with a state of the art laundry. CTS, a complete service from just one source.