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Pionieerspark Medical Centre can call themselves a proud owner of a 38kW photovoltaic grid feed system. Considerable savings on the monthly electricity bill are achieved as most of the electricity requirements are produced directly at the customer. Excess energy is fed back into the grid and credited on the monthly electricity bill by City of Windhoek.

The system consists of 144 265W PV modules mounted flat on the roof of the building with 2 Fronius three phase grid feed inverters and remote monitoring via the Fronius App on the cell phone. Remote monitoring allows CTS to advise the client on possible faults and recommended actions to be taken.

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

The installed photovoltaic system at Elavi Clinic caters for the power supply to the clinic as well as the nurse houses. A 6.2kW PV module array generates enough power for the energy requirements. Should this not be sufficient the batteries can be charged by a backup generator.

The system consists of the following:

• 6.24 kW PV array
• 2x Victron BueSolar 150V/70A MPPT regulator
• 600Ah Battery capacity
• Inverter/Charger, Victron Multi, 48V/8000VA
• System Monitoring (BMV700, Color Control GX)

Three localities in the Otjozondjupa region where successfully electrified by means of Off-Grid PV containers. The system sizes varied from 6kW, 12kW to 25kW of PV power. PV modules where installed on roofs of nearby houses, batteries, inverter/charger and switchgear are located in our proven design of prefabricated containers to keep the components cool, even in the hottest of climates.

The system is an AC coupled PV system with SMA Sunny Island (SI 8.0) inverter and SunnyBoys of various sizes. Communication between all components is based on a wireless RS485 solution from Phoenix Contact with a distance covered of 1.5km.

Sites that were electrified in the Otjozondjupa region are:

• Rooidag Hek 
• M’Kata
• Kukurushe

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.

Based on our excellent service and knowledge we have rendered to the Botswana Meteorological Department as well as University of Hamburg, CTS was able to secure the 2nd Phase of the manufacture, supply and installation of automatic weather stations in Botswana.

The stations supplied to make use of satellite communication due to the extreme remoteness of the sites, these were:

• Mababe (Savuti Marsh)
• Tubu (Okavango)
• Baines Drift (Eastern Botswana)
• Xade (Central Kalahari Game Park)
• Ngwaltle (Western Botswana)

These stations are not located at any Meteorological Department property, thus fences had to be erected for protection against animals.

Station design is based on our well proven tripod mast with all relevant sensors and a CR1000 logger as the processing unit. Data is transmitted at fixed timeslots allocated by EUMETSAT (Germany) on an hourly basis. Satellite transmission is based on a fire and forget principle, thus no remote maintenance can be done.

Weather data can be found at: http://www.sasscalweathernet.org .