Learn how pairing large-scale rainwater harvesting with solar panels creates the ultimate off-grid system for Australian rural properties.

In Australia, self-sufficiency isn't just a lifestyle choice; it’s a practical strategy for long-term resilience. When we look at a high-capacity setup like this recent installation of four 27,000L Crown Force Rainwater Tanks alongside a robust solar array, we see more than just infrastructure; we see the ultimate "Power Couple" of rural living.

By combining energy generation with massive water storage, you aren't just saving on bills; you are building a resilient property that works 24/7 to keep you independent.

1. The Multi-Tank Advantage: Why 100,000L+ Matters

For serious water security, volume is king. This setup utilises four 27,000L tanks to create a total storage capacity of 108,000 Litres.

Why choose multiple poly tanks over one large concrete or steel tank reservoir?

• Redundancy: If you need to clean one tank, you still have 81,000L of backup.
• Ease of Install: Poly tanks are easier to transport and position, especially behind existing sheds. Our tanks feature 4x moulded lifting lugs, making it easy to navigate them into position behind outbuildings where heavy concrete machinery can’t reach.
• Scalability: You can start with two tanks and add more as your catchment needs grow.

2. Plan Your Harvest: How Much Can You Catch?

Before you install, it’s vital to know if your roof area matches your storage goals. A common mistake is underestimating how quickly a large shed can fill a tank bank.

          Not sure which tank size you need? Use our Online Water Tank Size Guide & Calculator to input your roof dimensions and local rainfall data. It will help you calculate exactly how many litres you can harvest annually.

3. The "Plug & Play" Connection: Rain Tank Joiner Kits

To make four tanks work as a single, unified system, you need a connection that is both secure and flexible. We recommend the RapidPlas Rain Tank Joiner Kit.

Unlike rigid PVC piping that can crack if the ground settles under the weight of a full tank, our joiner kits use heavy-duty flexible food-grade hose. This allows the tanks to "settle" naturally while keeping water levels perfectly equalized across the entire bank.

·         Each joiner kit includes high-quality ball valves. This allows you to isolate any single tank in the line without having to drain your entire 108,000L reserve.

·         All RapidPlas rainwater tanks come standard with 2 BSP outlets at 3 & 6 o’clock allowing multiple tank connections

4. Efficient Pumping for Solar Properties

Moving over 100,000 litres of water requires a pump that won't punish your solar battery bank. We stock a premium range of Pumps that are ideal for solar-integrated homes.

While these are 240V pumps, they are highly efficient and designed to run seamlessly via your solar inverter.

5. Success Starts with the Base: Site Preparation

A 27,000L tank weighs 27 tonnes when full. Multiply that by four, and you have over 100 tonnes of weight sitting behind your shed. Correct site preparation is critical, we’ve put together a comprehensive video guide to show you exactly how to prepare a level, stable base using crusher dust.

WATCH: How to Prepare the Pad for your Rainwater Tank

6. Built for the Australian Sun

Since these tanks sit right next to solar panels, they are exposed to the same intense UV radiation. RapidPlas tanks are manufactured using our own RGBlend20 compound. The Raw material (polyethylene) is processed and ground in-house under controlled conditions and is made to the requirements of AS/NZS 4766:2006.

While your solar panels are soaking up the sun to power your home, your tanks are standing guard, engineered to resist fading, cracking, and degradation in the harshest Australian conditions.

Ready to build your own water powerhouse?

Whether you’re looking for a single tank or a multi-tank package like the one pictured here, we can help you find the right fit.

Browse our large tank range

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