Off-grid solar installation in the Garden Route South Africa

SPECIALIZED SOLAR SYSTEMS, renowned for its expertise in renewable energy, has recently completed yet another off-grid solar-powered installation for a client residing entirely off the grid. The picturesque location is a small holding nestled between Karatara and Rheenendal in the enchanting Garden Route of South Africa.

Off-grid energy systems play a vital role in supplying electricity to households and workshops, functioning independently without any connection to the public electricity network. These power systems essentially act as autonomous power stations, providing a seamless and dependable electricity supply comparable to that of the national electricity grid.

Whether it’s a modest residence, a sprawling estate, a commercial establishment, or an entire community relying on cumbersome diesel generators, off-grid stand-alone power systems emerge as the dependable, eco-friendly, hassle-free, and cost-competitive solution. Embracing these systems ensures a reliable power source for various applications, transforming the energy landscape for homes, businesses, and communities alike.

Summary of Equipment Used for the Off-grid Installation (detailed information below):

• 2250-Watt Array of Solar Modules (10-Year Guarantee, 25-Year 80% Yield)
• 1380-Amp hour 2V Cells at 24V with take-off leads, battery floats, log book, distilled water x a 20-liter drum, interconnecting cables, and hydrometer (1-Year Guarantee, 10-15-Year Lifespan)
• 85-Amp MPPT (Maximum Power Point Tracker) (5-Year Manufacturer Guarantee)
• Victron BMV700 Precision Battery Monitor (5-Year Manufacturer Guarantee)
• 5KVA 24V 120 Victron Energy Multiplus Inverter/Charger (5-Year Manufacturer Guarantee)
• System Programming and Maintenance/Owner Training

For more information on how to get off the grid, please complete one of the following:

• For a customized off-grid energy system quote, please complete this form link .
• For consultant assistance, please contact us at +27 (0)44 878 1126. 
• Visit our Off-Grid Garden Route Showroom in George at the following Google Maps location .
• View our complete residential off-grid solar systems at this link

View our online solar shop products: 

The breakdown of supplied off-grid power equipment for the Garden Route installation:

Solar Module Array

• To have an average input of 12 kWh/day from your solar modules in George, South Africa. Solar module arrays totaling 2250 watts were used. These solar modules have a 10-year manufacturer’s product guarantee and a 25-year terrestrial 80% yield.
• NB. Solar yield is determined by location, orientation, shading, panel surface condition, system usage, and weather conditions.
• 34° Tilt Angle Facing North with full-day exposure to the sun, i.e. no shading.

Battery Storage Capacity

1380-amp, 10-15 year life span, 2V Millennium Deep Cycle Batteries with interconnecting cables were used. These batteries have the capacity to store 9 kWh of usage per day and cycle the system at 27%, maintaining system efficiency and battery lifespan. Please note that actual cycle ratios may vary from installation to installation depending on system use. Please also note that during daylight hours, the system runs off PV as primary and batteries as secondary.

BMV-700 Precision Battery Monitoring

The essential function of a battery monitor is to calculate the ampere-hours consumed and the state of charge of a battery. Ampere-hours consumed are calculated by integrating the current flowing in or out of the battery. In the case of a constant current, this integration is equivalent to current multiplied by time. A discharge current of 10 A for 2 hours, for example, amounts to 20 Ah consumed. All our battery monitors are based on a powerful microprocessor, programmed with the algorithms needed for precision monitoring.

Standard information and alarms:

• Battery voltage (V).
• Battery charge/discharge current (A).
• Ampere-hours consumed (Ah).
  State of charge (%).
• Time to go at the current rate of discharge.
• Visual and audible alarm: over- and under voltage, and/or battery discharge.
• Programmable alarm or generator start relay.

Solar Charge Controller: MPPT (Maximum Power Point Tracking) battery monitoring 

• PV voltage up to 150 V
• The Blue Solar MPPT 150/70 and 150/85 charge controllers will charge a lower nominal-voltage battery from a higher nominal-voltage PV array.
• The controller will automatically adjust to a 12, 24, 36, or 48 V nominal battery voltage.

Ultra-fast Maximum Power Point Tracking (MPPT)

Especially in the case of a clouded sky, when light intensity is changing continuously, an ultra-fast MPPT controller will improve energy harvest by up to 30% compared to PWM charge controllers and by up to 10% compared to slower MPPT controllers.

Advanced Maximum Power Point Detection in case of partial shade conditions

• If partial shading occurs, two or more maximum power points may be present on the power-voltage curve.
• Conventional MPPTs tend to lock to a local MPP, which may not be the optimum MPPT.
• The innovative Blue Solar algorithm will always maximize energy harvest by locking to the optimum MPPT settings.

Outstanding conversion efficiency

Maximum efficiency exceeds 98%. Full output current up to 40°C (104°F).

Flexible charge algorithm

• Several preconfigured algorithms.
• One user programmable algorithm. Manual or automatic equalization. Battery temperature sensor.
• Battery voltage sense option.

Programmable auxiliary relay

For alarm or generator start purposes

Extensive electronic protection

• Over-temperature protection and power derating when temperatures are high.
• PV short circuit and PV reverse polarity protection.
• Reverse current protection.

CAN bus
To parallel up to 25 units, to connect to a Color Control panel, or to connect to a CAN bus network
PV short circuit and PV reverse polarity protection. Reverse current protection.

Pure Sine Wave Bi-Directional Inverter/Charger inverter

1 x 5000/24/120 Victron Multiplus Inverter/Charger
•    Continuous output power at 25’C (VA) per unit 5000
•    Continuous output power at 25’C (W) per unit 4500
•    Continuous output power at 40’C (W) per unit 4000
•    Peak Power (W) per unit 10 000

Multi-functional, with intelligent power management
The Multiplus is a powerful true sine wave inverter, a sophisticated battery charger that features adaptive charge technology, and a high-speed AC transfer switch in a single compact enclosure. Next, to these primary functions, the Multiplus has several advanced features, as outlined below.

Two AC Outputs

The main output has no-break functionality. The Multiplus takes over the supply to the connected loads in the event of a grid failure or when shore/generator power is disconnected. This happens so fast (less than 20 milliseconds) that computers and other electronic equipment will continue to operate without disruption. The second output is live only when AC is available on one of the inputs of the Multiplus. Loads that should not discharge the battery, like a water heater, for example, can be connected to this output (second output is available on models with a 50-A transfer switch only).

Virtually unlimited power thanks to parallel operation
Up to 6 Multi’s can operate in parallel to achieve higher power output. Six 24/5000/120 units, for example, will provide 25 kW / 30 kVA of output power with 720 amps of charging capacity.

Three phase capability
In addition to parallel connections, three units of the same model can be configured for three-phase output. But that’s not all: up to 6 sets of three units can be connected in parallel for a huge 75 kW / 90 kVA inverter and more than 2000 Amps charging capacity.

Power Control – Dealing with a limited generator, shoreside or grid power

The Multi Plus is a very powerful battery charger. It will, therefore, draw a lot of current from the generator or another supply source (nearly 10A per 5kVA Multi at 230VAC). With the Multi Control Panel, a maximum generator or shore current can be set. The Multi Plus will then take account of other AC loads and use whatever is extra for charging, thus preventing the generator or shore supply from being overloaded.

Power Assist – Boosting the capacity of shore or generator power

This feature takes the principle of Power Control to a new dimension. It allows the Multi Plus to supplement the capacity of the alternative source. Where peak power is often required only for a limited period, the Multi Plus will make sure that insufficient shore or generator power is immediately compensated for by power from the battery. When the load reduces, the spare power is used to recharge the battery.

Four-stage adaptive charger and dual bank battery charging

The main output provides a powerful charge to the battery system by means of advanced ‘adaptive charge’ software. The software fine-tunes the three-stage automatic process to suit the condition of the battery and adds a fourth stage for long periods of float charging. The adaptive charge process is described in more detail on the Phoenix Charger datasheet and on our website, under Technical Information. In addition to this, the Multi Plus will charge the second battery using an independent trickle charge output intended for the main engine or generator starter battery (trickle charge output is available on 12V and 24V models only).