Off-Grid Rainwater Harvesting for RVs
A compact and efficient rainwater harvesting system designed for mobile living in an RV. Capture, filter, and store rainwater for all your off-grid needs.
Core Components & Quick Specs
Rooftop Collection System
Modified gutters and downspouts to maximize water capture from your RV roof.
First-Flush Diverter
Automatically discards the initial, most contaminated rainwater.
Sediment Pre-filter
Removes leaves, twigs, and other large debris.
5-Micron Carbon Block Filter
Reduces sediment, chlorine, and organic compounds.
UV Sterilizer
Neutralizes bacteria and viruses for safe drinking water.
100-Gallon Storage Tank
Compact, food-grade water storage.
12V DC Water Pump
Provides pressurized water to your taps.
Technical & Engineering Deep-Dive
Flow Rate & Pressure Loss
A primary design parameter is the system's required flow rate, based on peak demand. This blueprint specifies components for 25-30 L/min. To achieve this, pipe diameter is critical. We mandate 3/4-inch PEX-A or copper for main lines to minimize frictional pressure loss. For every 100 feet, a 3/4-inch line has ~2-3 PSI loss, versus 8-10 PSI for a 1/2-inch line. This dictates the required head pressure from the pump.
Pump & Pressure Tank Sizing
The specified pump is sized not just for vertical lift but to overcome system-wide frictional losses, ensuring consistent pressure while operating efficiently. The pressure tank is vital, acting as a buffer to prevent the pump from rapid-cycling. The blueprint specifies a tank size for a 1-2 gallon draw-down before the pump engages, significantly extending its operational lifespan and reducing energy consumption.
Multi-Stage Filtration & Micron Ratings
This system employs a multi-stage filtration train. It begins with a 50-100μm sediment pre-filter, followed by a 5-micron filter. The workhorse is an activated carbon block filter (0.5 micron rating), which adsorbs chemicals, VOCs, pesticides, and unpleasant odors, and is effective against giardia and cryptosporidium cysts. This ensures water is not only clear, but chemically purified.
Final Stage: UV Sterilization
For any non-municipal source (rain, well, surface water), the final stage is a UV sterilizer. The lamp emits UV-C radiation (254nm), which scrambles the DNA of microorganisms, rendering them harmless. The chamber is sized to exceed the NSF/ANSI 55 Class A standard, providing a robust final barrier against 99.99% of all bacteria, viruses, and protozoa, delivering microbiologically safe water.