The global solar photovoltaic market size swelled to over $ 500 billion last year . This is because of the simple fact that solar energy is now the cheapest electricity in history. It seems that everyone is snapping solar panels up and you should really consider investing in solar yourself. New dark black silicon modules have better performance than even solar panels from a few years ago. Companies are repowering solar farms simply to make even more money. So often panels are being retired long before the end of their lifetimes. What do we do with the leftover solar panels? They still work just fine. A new study lays out how to give retired solar panels a new life by acting as electronic picnic tables.

Old Solar Panels Still Make Energy

In the old days, solar panels were often considered “retired” once they reached the end of their manufacturer warranty (typically 20–30 years), but in practice many still retain a substantial proportion of their original power output beyond that period. The annual degradation rates for crystalline-silicon cell based solar panels generally fall between 0.2% and 0.8%, with a global median of approximately 0.5% per year , indicating that even after 25 years many panels can still deliver 85–90% of their initial capacity, depending on environmental conditions and maintenance practices. Most solar panels on the market now are silicon based. For example, long-term field data from 23 solar power systems across different climates in the United States showed the median degradation rate was 0.5–0.6%/year, with numerous systems remaining fully operational after three decades. Plus, those are really old solar panels. Recent advancements in materials, encapsulation, and manufacturing processes have significantly enhanced module durability, with studies indicating that today’s solar panels can reliably operate for 30 years or more under typical field conditions.

In Canada to the north, the Ontario Society of Professional Engineers showed that many solar installations continue to generate usable electricity well past their 25-year warranty period, creating opportunities for repurposing retired modules in secondary applications such as community projects or educational infrastructure. In addition to end of life solar panels, because there has been so much improvement in solar panel technology over the past few years, there is a considerable amount of repowering solar farms as well – simply trading out older less efficient modules with higher efficient new ones. These old retired panels all have far more use in them. Although warranty expiration is often seen as the end of service life, many modules continue to operate reliably for years and are well-suited for reuse in open-source, small-scale systems such as solar-powered picnic tables.

Using Old Solar Panels To Make Electric Picnic Tables

We now use electric devices all the time and for that we need power. Most teens today when searching for power are like carnivores searching for meat when they need to charge their phones. This keeps most of us indoors more than is strictly healthy. A successful approach to provide power outdoors uses solar photovoltaic-powered picnic tables, but the existing proprietary designs suffer from high costs. A new study addresses this limitation by presenting the design of a novel open-source solar-powered picnic table fabricated from reused, decommissioned solar panels and recycled plastic lumber.

The open-source solar-powered picnic table acts as a conventional picnic table and provides electrical charging that supports learning and connectivity by providing outdoor power. The system integrates a 320 W solar panel, maximum power point charge controller, and 12 V lithium battery. It enables reliable off-grid power generation and storage.

The device was validated under real outdoor operating conditions using everyday user loads, including smartphones, tablets, and laptops as individual and multiple connected devices at different times of the day and night. You can build one for yourself from the plans in the study for <$450, which makes it cost less than 90–95% less than commercially available options. As the system design is open source this also offers new business opportunities for small firms to handle solar panels at the end of their lifetime to cut into the $350 million market for picnic tables. The system, built using recycled and repurposed components, further enhances sustainability while maintaining durability for outdoor deployment.

This is a classic example of dual use of solar – here both the energy and the surface to eat your lunch. The results of the study indicate that open-source solar furniture can provide an affordable and replicable approach for expanding renewable-powered charging access in outdoor environments.