The Zunino Institute’s cancer treatment medical facility in Córdoba, Argentina has recently solved their grid-electricity supply crisis by installing a large, ultra-reliable private power supply.
The battery-based energy system offers 180kVA – the maximum available from parallel-connected Victron Energy Quattros installed in a single system.
The problem the clinic had been experiencing was that their local energy grid was not always able to meet the clinic’s power demand. It has two Radiotherapy machines which regularly spike at over 80kVA on start up.
In addition to their critical treatment equipment, the clinic also use air conditioning units – together with all the usual power requirements of a busy medical centre from lighting and IT, to water-coolers.
Those peak-power spikes frequently pushed the clinic’s demand beyond the grid’s available power resource resulting in regular power outages at the worst possible time …at the beginning of their radio-therapy treatment.
Every time power is lost the treatment machines have to be restarted after which the sensitive equipment requires a settle-down period of 15 minutes before treatment can resume.
The situation was obviously extremely unsatisfactory. Quite apart from traumatising already-stressed patients it creates the knock-on effect of delaying appointments (which are booked back-to-back, owing to demand) resulting in inevitable end-of-day queues and tired staff.
The local grid couldn’t offer the clinic any hope of a future solution to the problem owing to limited built-infrastructure and the underground cable distribution for the local area.
The power grid is capable of supplying the clinic with a maximum 110kW – yet the clinic routinely needs in excess of 160kW. The clinic had been asked to reduce their demand, but this was incompatible with their objectives.
Victron Energy official distributer Baratec Solar – who work in Argentina and Uruguay – were asked to propose a solution.
The challenges Baratec faced were to provide a powerful peak-shaving system guaranteeing an uninterrupted power supply (UPS) from battery back-up capable of running the clinic, at full power for at least one hour from the moment of failure. Sensitive electronics require a near-perfect AC energy source if they are to perform as expected. Pure sine-wave energy from the Quattro Inverter/Chargers is ideal for such demanding equipment.
Consulting and Custom Design
Firstly, the supply was divided into two zones – critical and non critical.
The critical system offers peak shaving – limiting the power demand from the electricity grid – at the same time as instantly providing power backup in case of grid power failure. In the case of grid failure and an extended period of reliance on battery power, a back-up generator is programmed to start automatically.
The installation has been built using the following devices:
- 12 x Victron Quattro 48/15000/200-2×100. Four sets of three 15kVA devices have been configured for 3-phase supply. This arrangement also allows for a remarkable 2400A of charging capacity
- 4 x X LYTE 51,2 / 480Ah Lithium Battery which are specially designed to withstand high discharge currents to manage peak shaving.
- 1 x Color Control GX communication centre device provides local user-access to system information. It also harmonises all system components (Victron and third-party), allowing them to ‘talk’ to each other. The CCGX will send data to the internet allowing Baratec to monitor and programme the installation without leaving their office via the free-to-use platform Victron Remote Management (VRM)
- 1 x Battery Monitor BMV 712 Smart. The battery monitor records and stores a wealth of system data including: Battery voltage, current, power, ampere-hours consumed and state of charge; it also calculates remaining run-time at the current rate of discharge. It has a programmable visual and audible alarm; and a relay can be programmed to turn off non-critical loads or to run a generator at a set-point.
- 1 x Orion-Tr 48/24-5A DC-DC Converter. The Orion has been configured to guarantee an uninterrupted power source for the control board for air conditioners and other non-critical load relays.
A testament to the skill of the Baratec engineers is that they make their own lithium batteries which they sell under the brand name of X LYTE. In this system a 1920Ah battery bank stores more than 100kWh of energy.
The greatest challenge of the grid-tied installation with back up generator, however, is that the power feed from both the grid and the generator is from a single inverter input.
Let’s hear from Sebastian Barratero to tell us how that works:
Due to the physical characteristics of the location, the switch point between the electrical grid and the generator was positioned at a considerable distance from the inverters. For this reason, we had to utilize the existing switchgear and channel both energy sources through the same inverter input. Initially, we encountered unexpected challenges due to the age of the switchgear. During transitions from the grid to the generator, it resulted in coupling failures with the inverters. After conducting numerous tests, we identified the issue with the switchgear. Consequently, we replaced it with two new independent contactors, enabling smoother transitions between inputs. Furthermore, we leveraged configuration assistants on the Quattro inverters to tailor the maximum current input based on the connected source at any given time. This approach enables us to perform necessary peak shaving power limits when connected to the grid and increase the limit to draw more power when utilizing the generator through the same input.
Baratec Solar – a family business
In the early 1990s, brothers Mario and Fabian Barattero founded Baratec Rally, a venture dedicated to constructing and developing rally cars culminating in 2001, with BARATEC Suspension for racing cars and other hydraulic systems.
In 2015, Fabian Barattero bought a remote building plot on the shores of Cordoba lake, far from the grid energy. An off-grid solar power system from a local provider solved the immediate power need but brought with it so many issues that Fabian decided to research the best solutions, worldwide, and bring his own problem-solving skills to the challenge. Recognising the potential of solar energy for Argentina, he formed Baratec Solar to offer high-quality products to the local market, provide reliable and efficient solutions to domestic, commercial and industrial users. With their engineering background Baratec offers their own-manufacture lithium batteries in Argentina and Uruguay under the brand name X LYTE.
The Zunino Institute clinic’s new system – devices and associated cabling – had to be installed in the existing facility which is a traditional building (it was formerly a grand house) whose space is already utilised to near-capacity. Baratec eventually found space on the second floor of the building which presented its own challenges because 12 x Quattro 15kVA had to be carried up two flights of stairs. A quick look at the datasheet tells me that these devices weigh 72 kilos a piece!
At the time of installation this system featured the largest battery Baratec had built. The battery supplies the Inverters with a DC current of 2000A – for which a custom busbar was built. More recently, Baratec have built even larger battery storage systems.
It’s gratifying to hear that this maximised system has been running for two years, faultlessly. It’s a testament both the reliability of the equipment and the quality of the site installation and planning.
As a result the efficiency of the clinic has been enhanced, and patients can be assured of timely treatment. The designed redundancy is able to absorb peak-loading spikes and deliver clean power under all grid conditions. And to be doubly-sure of reliable service under any conditions, the 180kVA generator will start automatically – triggered by a programmed relay if ever the battery bank falls below a preset state-of-charge.
Not only has this installation met the clinic’s every requirement, but it has brought a serendipitous advantage for the local community: the grid in their area was fairly reliable before the installation – now it’s perfect!