Can we 3D print trees? Well, technically we can’t print real trees, not even with advanced bioprinting techniques, but that doesn’t stop scientists at the Technical Centre of Finland (VTT) come up with alternatives. What they have come up with, is a 3D printed ‘tree’ with organic, solder cells. The tree uses its cells to harvest solar energy, and the vibrations it captures – think of the blowing wind – produce kinetic energy. This 3D printed tree just a prototype, but the idea of the scientists is to use these kinds of ‘trees’ on a wider scale to harvest energy on an eco-friendly way.
These trees can be used indoors and outdoors. They store the energy they harvest and turn it into electricity. As we mentioned, the leaves are made of solder cells. The tree thunk, however, is partly made of real wood. The team used a wood-based composite for the trunk, which they developed themselves. In other words: it smells like wood. The electricity generated by the leaves can be used to power mobile phones, LED lighting or thermometers. VTT is the largest multi-technological applied research organization of the Northern part of Europe. It is property of Ministry of Employment and Economy.
VTT came up with a mass production technique to create the leaves. They are flexible solar panels and in combination with wiring they can conduct energy into a converter. This converter transports the energy to all preferred devices, such as your mobile phone. The leaves have a separate power converter and a multi-converter system. This enables them to harvest energy from multiple power sources. Apart from sunshine and wind, a leaf is also fed by temperature fluctuations.
Each leaf’s solar panel is just 0.2 mm thick, and it consists of electrodes and polymer layers. Thanks to the graphics, they look like actual leaves. Well, leaves 2.0, maybe. The leaves and its layers are 3D printed, and each leaf includes detailed connections for the wiring and photovoltaic cells. The surface area of these cells? Exactly 0.0144 square meters. The company claims 200 of its leaves are good for 3.2 amperes of electricity. It they are placed on an outdoor location, one square-meter of leaves can generate 10.4 watts – in case of a sunny climate.
Normal trees grow new leaves every year, but unfortunatly technology hasn’t come that far yet. These 3D printed leaves work for a couple of years, and then they need to be replaced by new ones. Nevertheless, the scientists claim their leaves can be fully recycled, so new ones could be produced with old materials. Thanks to their roll-to-roll manufacturing method, they can produce up to 100 meters of leaf rolls (see image above) per minute. That’s what we call rapid additive manufacturing.
Credits images: Technical Centre of Finland (VTT).