When we think about how to meet global energy needs sustainably, it’s certain that solar energy will play a key role. A direct way of harnessing the sustainable fusion reaction taking place in the Sun, solar energy technology was first developed for use in space where fuel is difficult to replenish. Since then, photovoltaics (converting light into electricity) have improved in maximum efficiency from around 1% to 45%. A ‘quick’ calculation will tell you that we would need to cover just 1% of the surface of the Sahara with solar panels to satisfy our current, worldwide demands with renewable, sustainable and pollution-free energy (providing that you disregard the production of the required solar panels, of course). So why haven’t we done this already?

The challenge with photovoltaics

There are many different types of photovoltaics and high-efficiency solar energy is generally associated with those based on silicon. Mono-crystalline silicon solar cells are very efficient as they avoid energy loss from charges crossing grain boundaries. The silicon crystallisation must be controlled so that only one crystal is seeded, meaning that all impurities must be avoided during fabrication. Silicon can be very expensive to process for this purpose and there’s a forecasted shortage in supply based on the projected growth of the solar cell market. An alternative would be to use multi-crystalline silicon solar cells — these have the disadvantage of grain boundaries but are still relatively high-efficiency and simpler to manufacture.

Another cheaper but less efficient alternative is thin films such as organic or perovskite photovoltaics, which include harnessing the electrical properties of certain polymers or perovskites. These materials can be soluble, meaning that solar cells can be printed. Layers of the conductive materials are deposited sequentially and quickly over large surface-areas. These typically operate in the glassy or semi-crystalline phase, requiring less demanding production. Printed photovoltaics can be flexible and even transparent.

Securing patent protection

Solar energy certainly has great potential but ultimately, more innovation is needed to fully realise this. A promising development is using solar cells more widely, which could supplement domestic energy provision, reduce a country’s reliance on imported energy and supply individuals with the ability to reduce their energy bills, or even break away from the grid altogether.

New implementations of solar cells may be patentable if they use known elements in a new way. For example, solar panels incorporated into car exteriors, aeroplane wings, roofing tiles, the walls of buildings, windowpanes and smaller devices such as remote controls have all received patent protection and been marketed.

For a patent to be granted the invention must be new and not an obvious development from what already exists in the public domain. If you’re wondering whether your implementation is patentable, consider whether the combination of known features provides a technical effect which is greater than the mere sum of the technical effects of the individual features. If this is true, then it may be a patentable invention.