This summer has been one of the warmest on record in the northern hemisphere. 97% of Greenland’s surface ice thawed in an historical four days. Maybe it’s time to take a look at the grass roots of the green world to see what some folks are doing on a small scale level to tackle climate change.

Self-Watering Greenhouse
As part of a university project with the University of Central Lancashire, one green-hearted grandma, above, decided to build a greenhouse almost entirely of plastic bottles. Although most bottled greenhouses are made by primary school children, this one possesses the incredible ability to water itself without human assistance.

Although the 68-year-old did indeed begin the project as part of her masters degree, the greenhouse highlights the versatility of how green thinking can be implemented in every part of our lives.

Consisting of 1400 plastic bottles, Linda Woollard has for the past year and a half been able to supply her friends with seeds and produce that has been lovingly and naturally cultivated within her greenhouse.

But how does it water itself?

‘By design’ is the answer. Due to the rounded shape of the bottles and their intricate placing within the structure, they allow tiny droplets of water to pass through and therein irrigate the greenery bellow.

Did you know however, that standard greenhouses could be themselves recycled? Indeed, one greenhouse by Hartley Botanic was sold on Ebay by its owner for 100 percent profit after 32 years of use.

Solar Thermal Plastic Bottle Water Heater
Utilizing recycled bottles again, while at the same time discovering an innovative invention from yet another retiree, this latest invention is pretty remarkable: a solar thermal heater made from water bottles.

Retired Brazilian mechanic, Joe Alano, with his solar thermal plastic water bottle heater.

Attempting to tackle recycling issues in Brazil, retired mechanic Joe Alano, above, has invented a cheap alternative to corporate solar thermal panels.

Kids putting together Alano’s solar water heater. Photo: Renewable Power News.

Using only basic knowledge of heating systems, along with 100 plastic bottles and 100 milk cartons, the invention not only worked, but won him the Superecologia prize for renewable energy products.

Amazingly, the bottle-powered heater can save costs by up to 30 percent. Not bad for a bit of old plastic.

An Energy-Making Hotel 
Not every hotel offers you a comfortable bed and at the same time the opportunity to help save the environment. The Crown Plaza Copenhagen Towers offer guests that very privilege with their electricity-producing exercise bikes.

With monitors installed into the bikes, any guest who produces more than 10 watt hours will be rewarded with a free meal. Excellent if you’re looking to keep fit on your holiday.

Achieving the wattage needed for the free meal is also surprisingly easy as cycling at just 9 mph for an hour will produce around 50 watt hours–begging the question as to why more businesses haven’t taken up this wonderful offer.

3D Solar Panels
If the thermal solar panels didn’t impress you and the electricity-producing bikes didn’t inspire you to have a go yourself then this invention may do it for you.

Although the invention itself is pretty fantastic, what adds depth to the matter is the inventor himself: 12 year old William Yuan.

12 year-old William Yuan invented 3D solar panels. Photo: Allvoices.com

By simply observing the way in which trees absorb light and the structure in which they stand, the Oregon youth managed to device a cell which absorbed both visible and UV light. The 3D cells are capable of utilizing up to nine times more light than existing 3D cells.

Although not yet on the market, Yuan received a nice $25,000 scholarship for his research along with a Davidson Fellow award.

What cool green inventions have you spotted?