Energy Management for a Safari Lodge

Electricity does not come "from the socket", from the grid, everywhere in the world. And it isn’t only in settlements in the middle of nowhere or raw material extraction far from civilization. Remote holiday resorts need electricity too. Until now, this was provided by diesel generators - noisy, polluting and increasingly expensive. But there are hybrid solutions that use renewable energy to drastically reduce or even completely replace diesel consumption. It is made possible by a combination of energy management and measurement technology.
Luxury resort is an incomplete description of Cheetah Plains Lodge in South Africa. Guests who book a safari here stay in villas with their own wine gallery, curated art collection and, of course, a private chef. The tour goes off-road under expert guidance with electric Land Cruisers; a quiet and emission-free form of transport that almost guarantees Big Five sightings.
However, a unique safari experience is not the only thing that the house management and the discerning guests value. Environmental management and sustainability are also a must. This includes grey water recycling and using construction materials such as energy-saving glass, which reduces heat transfer through the windows.
One problem still had to be solved: obtaining a sustainable and secure power supply. Although there was a single phase connection from the local energy supplier, the capacity was limited and there were considerable voltage fluctuations. This type of supply was unable to cope with the increasing energy demand from cooling systems and charging stations for the e-vehicles. Therefore, the owners commissioned the South African solar power expert Blockpower and the German microgrid integrator Dhybrid to install a three-phase energy system with a photovoltaic plant and a microgrid energy storage system based on lithium-ion batteries. A diesel generator only needs to cover possible supply shortfalls in case of an emergency.

Diesel only for emergencies
With the new system, Safari Lodge meets most of its energy demand with the solar power system, which produces a total of 300 kWp. 260 kWp rooftop systems have been installed on the carports and the employees' accommodation (image 1). On top of this, 40 kWp is produced by three dual-axis trackers (image 2). They feed the lithium-ion storage with a capacity of 1,027 kWh (image 3), which in turn supplies the grid-forming, bidirectional battery inverter. With a peak output of 250 kW at stable output voltage and frequency, it provides ample reserves for a 3-phase power supply. Even larger consumers, such as cooling systems, engines or the charging stations for the Land Cruisers, can be reliably operated using this system. The inverter and batteries are housed in a 20-foot energy container. It has been equipped with air-conditioning and an extinguishing gas system and was delivered fully wired.
A 150 kVA diesel generator is used for emergency power supply. The generator was upgraded from a stand-by generator to a generator that can be controlled remotely and is suitable for parallel operation. However, it is only used in exceptional cases. The system runs on almost 100% renewable energy. In addition, the regional energy supplier's single-phase line can also be connected.
Much more than measured values: Janitza creates clarity in the data jungle
Having a quick overview of the essential functions and the operating status of the system at all times is indispensable for the crew on site. On the other hand, the specialists at Dhybrid need more detailed information for remote maintenance. With the measurement devices from Janitza, both are possible. Alexander Wagenhuber from Janitza explained: "Unlike many other devices on the market, we offer four ports, sometimes even more. This makes communication with several systems easier. This way, Dhybrid's SCADA and our GridVis software can even access a meter at the same time." Tom Fricke added: "GridVis is a good tool, especially for initial commissioning. You can quickly see whether the measured values fit and can log them as well. The larger devices even have a dedicated webpage, which we use to generate power quality reports in addition to event logging." As a result, Janitza's hardware and software have made it possible to implement two independent measuring systems. Technicians on site receive all the necessary information for operations and servicing. In addition, the specialists at headquarters in Gauting can connect remotely and give guidance on tricky work. The combination of the UMG measurement devices from Janitza and the corresponding GridVis software allows a much higher data transmission rate than a SCADA system.
The total solution offers Cheetah Plains a whole range of advantages, including the integration of 3-phase consumers, increased peak power supply and a stable system voltage and frequency. Independence from the grid does not come at the expense of nature. Guests and hosts can enjoy the fact that the power supply provided for their comfort and to allow them to travel around is generated directly on site using solar energy.