Home | Central Technical Supplies

In early 2017 Stier Vente Chartered Accountant did take the decision to move to renewable energy. A 17kW grid feed system was installed on the roof of the office building to reduce the monthly electricity bill.

A total of 67 260W PV modules and a SMA SunnyTripower 17kW inverter was installed. Remote monitoring allows CTS to advise the client on possible faults and recommended actions to be taken.

DeBeers Namibia published a tender for the supply and installation of a weather monitoring system at the Oranjemund Airport. CTS was awarded the tender based on price, knowledge of the meteorological measuring equipment as well as quality of products. At time of installation the station was the most advanced aviation weather station in Namibia.

Technical Details of the system installed:

• Ceilometer at end of runway 20 to measure cloud height at three levels up to 7,500m
• Runway Visibility and Present Weather sensor at stop end of runway 20.
• Present weather sensor monitors 7 different types of precipitation
• visibility sensor takes background luminescence into account
• Wind speed and direction a touchdown runway 20.
• Wind speed and direction, rain as well as barometric pressure at stop end runway 20
• AviMet server for processing of all data
• 3 workstations spread along the buildings for weather monitoring and supervision purposes
• ATIS voice system transmitting on aviation frequency as well as telephone dial in the current weather conditions

All communication between the equipment and the AviMet server is based on wireless transmission to reduce cabling costs.

The weather information can be picked up rough 100 NM away from the airport by all approaching aircraft.

A 200kW PV peak grid tied PV system was installed at Quality Tyres Lafrenz Industrial Area. Remote monitoring of all 10 inverter allows for early fault detection and system degradation as well as maintenance planing.

System Specifications are:

• 680x 295W Canadian Solar modules
• 10x Fronius Symo 20.0-3 Grid Inverter
• Roof mounting structure for IBR roof sheeting
• AC surge protection
• configured for remote monitoring

Ministry of Agriculture through, through SASSCAL funding, did acquire 3 automatic weather stations in 2018 which where finally installed in 2019 after sites have been determined. These stations from part of the existing SASSCAL weather station network that has been established over the past years. All stations conform to SASSCAL requirements and are inline with WMO standards.

The stations are installed at :

• Dudukabe (Zambezi)
• Okalongo (Ohangwena)
• Omafo (Ohangwena)

Station info can be obtained from www.sasscalweathernet.org

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.

Various small off-grid PV systems, also referred to SHS (Solar Home Systems) have been supplied country wide. These systems are typically based on small high efficiency lithium ion batteries as storage solution and Victron components such as solar charge regulator, inverter and monitoring devices.