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Making Hot Water if the Grid Goes Down – Cheap Easy DIY

Have you ever thought what you would do if the electrical utility power service was down for a week or a month, and you couldn’t easily get a hot shower?

Believe it or not, there is a cheap and easy DIY solution. If you already have a few solar panels, they can heat water for a shower, washing dishes, or just any need that you have.

The Solution

This is so cheap and simple, it’s ridiculous – a plastic bucket or 10 gallon plastic tote (storage container) will do the job.

Next, add a DC-rated hot water heater element. They can run off of 12-48 volts DC. You take one of those (which type depends on the VoC of your solar panels) and install it in the bucket.

In about an hour, that water can be heated up and ready for use. No electronics needed. This is a PV2L (PV To Load) appliance for very little money. A simple camp shower or any pump will draw the water out and make hot showers possible with low-tech equipment. I personally did not use a thermostat because I supervise the water heater at all time. This type of setup should not be left unattended for any reason.

Safety Warnings

Of course basic safety precautions must be taken. DC voltage in a bathroom is nothing to treat carelessly. 48V is considered the edge of safety but it can still give you a zap when touching bare or wet DC electrical wiring.

WARNING: Do not attempt to use a 120/240V element and high DC voltage by putting panels in series. DC Voltages above the ~48 region can be lethal.

Optionally, the performance of the solar electric HWH can be enhanced with simple foam sheet insulation. Any scrap foam will do, or even wrap a blanket or towel around the container. Avoid contacting the DC terminals with the insulation, keep those dry and covered.

Watch this concept demonstrated

Want to see this simple and cheap HWH in operation? I made one in my workshop as a demo of the concept. It worked extremely well. The video is below. YT basically ignores this video, so if you watch even part of it it really helps me out 🙂 Thanks for reading! DD


About the Author:

DD Solar (a nickname) has over a decade of experience in solar power and renewable energy, and over 25 years of experience in the Information Technology industry. He currently operates a YouTube channel called Solar Power Edge (formerly known as DIY Solar Power Edge and DD Solar Channel) and documents some of his projects and prototypes there. (C) 2022 DIY Solar Power Edge channel / DD Solar channel / SolarPowerEdge BLOG All rights reserved. We reserve all rights.
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