☀️❄️ To beat the heat, we're experimenting with a water cooled shirt.

It is similar in concept to cooling garments worn by astronauts but utilizes common components anyone can buy including aquarium tubing, a 12v DC water pump, and cheap rechargeable 12v batteries.

It's still being tested and a few versions are likely to be made including one using a sewing machine instead of sewing in the tubing by hand!

❄️ In 41C (105F) weather this cooling-system made of common-place items is actually working.

To do:

▪️Extend duration from 10 minutes to 30 or even 60 minutes at least between adding addition ice;

▪️Create a smaller more practical carrying method (belt system perhaps);

Industrial design isn't about getting it right the first time, it's about getting something going to learn from and get it right in the end.

⚡️☀️solar power: a note on inverters

One of the first problems we ran into when trying to run corners of our house with solar power was a loud buzzing sound coming from the TV and power strip.

It turns out the initial inverter (pictured on the top) that changes DC to AC power is a modified sine wave. It is square wave with additional steps to approximate a sine wave.

For many electronic devices in your home, you need a pure sine wave inverter to produce a waveform similar to what the grid provides. That waveform looks like smooth curves as seen on the bottom.

We're unsure if our current inverter is doing any damage but the buzz sounds terrible.

Pure sine wave inverters are a bit more expensive but will provide the highest quality AC for your home devices.

☀️🔌 Solar Power Bank Project

(if none of this makes sense, don't worry, we're going to do a whole video on this project once it's complete. It's still being pieced together and tested).

▪️A second battery has been added in parallel;

▪️Bolt connectors have been used to replace default clip connectors (more secure & simplifies connecting more than one wire per teriminal);

▪️Adding another battery in parallel should provide more amp hours for system use;

▪️This solar power bank is used primarily for running basic systems in a temporary power outage;

🔌☀️ Solar Power Bank Test

▪️With 2 batteries we managed to run the living room at night (excluding the air conditioner) for over an hour;

▪️There was still power left in the batteries but 1 hour was the goal for this test, simulating a power outage at night;

▪️During the day, the solar panel itself helps extend the system even with just one battery;

▪️Power in and around Bangkok, Thailand is very reliable and in almost 20 years here, I've never seen it out for more than an hour, usually 10-15 minutes once in a long while;

Next​ step will be to document how to make your own solar power bank.

Now that we know it works, we can make additional systems for larger scale solar applications outside.

Stay tuned.