In this instructable , I'll show you how to make a solar water filter with nothing more than a couple of bottles and a short length of PVC pipe.

Here's what you'll need to make this.

2 plastic/bpa-free/glass bottles with screw top lids.
One short length of 20mm pvc pipe that's just a bit shorter than the bottles you are using.

Tools

Drill and 20mm drill bit (or anything else you can use to make a hole)
Hot glue gun (optional but not required)

Step 1: Watch the Video!

Watching a video seems to be the way the cool people learn things on the internet but, if you're old-school, you can enjoy reading the written instructions that follow!

If you can't see the video above, find it on my channel here - http://bit.ly/1ODLIwG

Step 2:

Choose 2 bottles about the same size.

I found 500ml plastic water bottles and removed the plastic screw tops in preparation for the next step. (I got these for free- score!)

Step 3:

Once you have removed the screw tops, you will want to temporarily fasten them together using some hot glue. Once they are glued together as shown above, drill a 20mm hole straight through both screw tops.

Although hot glue isn't necessary, it may help to find a way to fasten the screw tops together to ensure that the holes line up perfectly later on.

Once the you've drilled the hole, you can remove any excess glue or leave it on. The glue makes no contact with the water, so it's still 100% safe.

Step 4:

Next, cut the pvc pipe to a length that is slightly shorter than the bottle.

Then press-fit the screw tops onto the pvc pipe and screw on the bottles as shown.

Step 5:

We're ready to test it!

Firstly, we want to make sure we orient the filter the right way. The video below shows this well but you can make reference to the images above to figure it out. Make sure the bottle with the pipe in it is positioned at the top or this filter will not work as described!

Once you know which side is UP ,fill the lower bottle with the water you need filtered and then screw the upper assembly back on.

Leave the filter in the sun for a few hours to a day (depending on temperature). Once enough time has passed, you will find that the water heats up and evaporates through the tube, leaving the dirt behind. The vapor then condenses and clean water collects in the catchment bottle of the upper assembly.

If you liked this instructable, be sure to leave your feedback in the comments section.

If you've read this far and you're still unsure of how this works, just watch the video below or on my YouTube channel.