A large portion of the worlds population still spends more than half of their income on food. Growing your own food means that you can use a larger share of your income for education, healthcare and other things.
However the farther you live from the equator the larger the effect of seasons will be, shortening your growing period.
With this wall-sided greenhouse you cannot only expand your growing season but it will also help warm your house!
The added benefit of the regulating done by the Arduino is that you can be away to work for the day(s) and won't find your plants shrivelled by the heat or drought when you come back.
In the picture below is an example of how it could be, and in the following steps certain aspects will be further explained.
Step 1: The Greenhouse
The best way to build a greenhouse would be to use glass and metal or wood, but those materials are too expensive for a lot of people on this globe so smart use of local materials and trash is needed.
For example discarded plastic bags can be found anywhere for free. Collect a bucket full of clear or white ones, cut them open and glue/stitch/staple them together and you have something you can use instead of glass. Granted, it won't work as good as glass but you'll be surprised how much heat it can retain.
For support you can use bamboo, wood or something local that grows quickly.
It would also be a good idea to build the greenhouse against a dark wall, this will receive and store solar warmth during the day and slowly release it to the greenhouse and room on the other side during the night.
Step 2: Guts of the System
So now let's take a look at the stuff that powers and controls everything.
The core will be a Ready Set Solar Kit that powers an Arduino, an air humidity and temperature sensor, a ground humidity sensor, a water pump and a fan.
The Arduino will be the brain of the system, because it is power efficient and cheap. It will monitor the sensors and depending on the input it can decide to run the pump to water the plants or run the fan to lower the humidity and temperature.
The fan an temperature sensor can be salvaged from an old electronic device or even a wrecked car, for water storage practically everything that holds water can be used.
Apart from Solar Kit, the Arduino and maybe the humidity practically anything can be salvaged as components from broken stuff or bought for a very small price.
The goal for this concept was to create a greenhouse that almost anybody can build with most of the parts being local and free.
PS. Please forgive any language errors, English is not my motherlanguage.
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