Going off grid with Vic?

Victron is a well known brand of inverter and hardware known for its performance and robust solutions.
Victron offer a wide range of kits parts to make a more complete solution and is a premium brand, here are Renewsolar we are not fans of the pricing for a lot of their hardware, but the market influences people and so we meet that need.

The multiplus II is a 5000w 48v inverter.
The Victron MultiPlus-II is an inverter/charger that combines the functionality of two separate Victron products: the MultiPlus and the MultiGrid. This means it has all the features of both, making it a versatile device for managing your home’s energy use.

Here’s a breakdown of the key features of the Victron MultiPlus-II:

Inverter:

• Converts DC power from batteries to AC power that can be used by your appliances.
• Provides uninterrupted power supply (UPS) in case of grid outages.

Charger:

• Charges batteries using AC power from the grid.
• Optimizes self-consumption by using excess solar power to charge batteries before drawing from the grid.

Additional features:

• PowerControl: Limits the amount of power drawn from the grid by supplementing it with battery power. This is useful for preventing overloading the grid connection.
• PowerAssist: Boosts the capacity of a limited shore power connection (e.g., campsite) with power from the batteries.
• Remote monitoring and control: The MultiPlus-II can be monitored and controlled remotely via Victron’s smartphone app (VRM app) or the VRM online portal. This allows you to see real-time system data and adjust settings as needed.

Two versions are available:

• Standard MultiPlus-II: Requires a separate GX device for advanced features like remote monitoring and PowerControl/PowerAssist with external current sensing.
• MultiPlus-II GX: This version has a built-in GX device, so all the advanced features are readily available.
  
  product data sheet

We offer a range of batteries and we would suggest having a larger system over all with the Victron. This means that the 15kwh battery we offer would provide a good duration of power
15kWh Battery 48v — RenewSolar

Unfortunately, it’s impossible to give a general runtime for a 15kWh battery with a Victron MultiPlus-II without knowing more about your power consumption.

Here’s why:

• Appliance Draw: The biggest factor is the wattage of the appliances you’ll be running on the battery. A system running a small fridge and lights will have a much longer runtime than one powering a large air conditioner and a clothes dryer.
• Inverter Efficiency: Inverters aren’t 100% efficient. There will be some energy loss when converting DC battery power to usable AC power.
• Depth of Discharge: Most batteries shouldn’t be completely drained to preserve their lifespan. The usable capacity is typically around 80% of the total for lead-acid batteries and can be higher for lithium-ion batteries as well as the LFP battery from us.

However, here are some ways to estimate runtime:

1. Identify Appliance Wattage: Make a list of the appliances you plan to power and find their wattage ratings.
2. Calculate Total Load: Add up the wattage ratings of all the appliances you want to run simultaneously.
3. Factor in Efficiency: Most inverters have an efficiency rating around 85-90%. Multiply your total load by 1.1 to 1.2 to account for this loss. (e.g., 1000W appliance * 1.1 = 1100W)
4. Usable Battery Capacity: Multiply the total battery capacity (15kWh) by the depth of discharge (typically 0.8 for lead-acid).

Example:

Let’s say you want to run a 50W LED light and a 100W refrigerator (total load = 150W). Accounting for inverter inefficiency (150W * 1.1 = 165W). With a lead-acid battery and a depth of discharge of 0.8, your usable capacity is 15kWh * 0.8 = 12kWh.

Estimated Runtime:

Usable Capacity (12kWh) / Load (165W) = ~72.7 hours

This is a very rough estimate. Your actual runtime will vary depending on how long you run each appliance and how efficient your inverter is, Higher loads tend to reduce the battery capacity, but we also used larger batteries that we say 🙂 .

Victron solar input
the multi plus does NOT have a inbuilt MPPT charge controller and therefore you would buy additional hardware for this purpose. The solar charge controller. Higher voltage charge controllers are best in the UK.

The Victron SmartSolar MPPT RS is a “standard” power that you find in most other AIO inverter chargers. With 450v and 100 amp, it is capable of charging at 4.8Kw. Victron says they are Available in a 5.76kW and 11.52kW models, the price is around £1000 for this must have item.

Due to the limits and requirements of off grid solar, you are likely to require more solar inputs to charge the battery around the year, therefore BlueSolar MPPT 150/35 – Victron Energy would give you a “normal” amount of power limiting your array size to 3 panels per charge controller. this is due to the voltage limit of just 150v, with solar panels being around 38v you can see how this becomes an issue.
they also make a 250/100 which is just £500 added costs for a more usable device allowing you to have 6 solar panels within your array, which is around 2500W. You could parallel the array giving you twice the current and allowing 12 solar panels to operate and that total of 5kw of solar.

The victron has some features that allow you to add a micro inverter as a input, this will allow you to add micro inverters should you need to have a secondary array. As you may have read, we promote dual arrays for summer and winter to maximise your yields and to make you less grid dependent.

As a kit, it is hard to put the kit together due to the range of hardware that is available. you could buy the much lower all in one from Sunsynk/Deye for example their 8kw inverter. This has built in dual mppt as well as the aux input, its grid tied and also has EPS meaning that you can run off grid also.

If I were to example a kit based on Victron 48/5000 it would comprise of two charge controllers, the multiplus2 and 30kwh of battery storage with 12 solar panels.
This would have a base price around £7355.