What made solar power the most desirable energy source on the planet?

As of the mid-2020s, solar energy emerged as the most affordable electricity generation source globally, outpacing all other forms of power. With lifespans extending to between 30 and 40 years for solar panels, the looming question remained: what happens when they reach the end of their operational lives? Experts predict that by 2050, approximately 160 megatonnes of solar module waste could accumulate. While this figure pales in comparison to the waste produced by fossil fuel energy sources, it signifies a considerable environmental challenge.

Imagine the potential benefits of solar panels designed for self-repair and even self-assembly.

By the mid-2030s, innovations had paved the way for biological photovoltaics (BPVs), referred to as living solar panels, to be widely deployed across the globe. The aesthetically pleasing design of BPVs fueled a rapid adoption, particularly in urban areas embracing YIMBYism (“Yes In My Back Yard”).

The primary advantages of BPVs were felt in rural and off-grid communities, particularly in sub-Saharan Africa, where these panels provided essential energy for devices like phones and computers, circumventing traditional battery dependence. As the technology evolved, historic structures benefited from retrofitted BPVs incorporated into green roofs and walls; architects began designing new buildings to integrate these living solar panels from the outset, thus enabling greater independence from conventional power grids. This shift also fostered biodiversity, significantly enhancing community well-being.

BPVs function similarly to fuel cells, where electrons are transferred from a cathode to an anode, generating electrical currents. In this biological framework, photosynthetic organisms produce electrons, which are then channeled to the anode.

Research dating back to 2011 had highlighted the phenomenon of electrical leakage from cyanobacteria under sunlight. When cyanobacteria are placed on electrodes, their natural processes can yield current to power small devices.

Although the initial current output was minimal, substantial advancements came from scientists like Chris Howe at the University of Cambridge, who modified cyanobacteria to optimize their electron output. In 2022, his team successfully demonstrated that it was feasible to power electronic devices solely through photosynthesis. Progressing from these early innovations, scientists subsequently learned to scale this energy harvesting, allowing BPVs to be installed on a broader scale worldwide.

<figure data-component-name="pull-quote" data-quote="Members of Homo photosyntheticus vowed to limit their electricity use only to that derived from photosynthesis”>

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Members of Homo photosyntheticus vowed to limit their electricity use only to that derived from photosynthesis
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The immediate advantages included a significant decrease in demand for coin-sized batteries that powered various electronic devices. By 2025, small batteries constituted 3% of the global battery market, generating around 10,000 tonnes of waste annually.

As BPVs became more powerful, they were capable of energizing larger devices such as smartphones and refrigerators. Electric vehicles began to recharge from these biological solar arrays at designated locations, leading to reduced demand for scarce metals like lithium and manganese.

Remarkably, these biological solar cells continued to work even during the night. They metabolized compounds synthesized during daylight to generate a comparable electron output in darkness, maintaining power availability.

The proliferation of living solar panels transformed urban landscapes as city planners integrated greenery into public spaces and streets. Cities flourished with vibrant greenery, promoting biodiversity while enhancing the city’s overall aesthetic as insects buzzed and birds sang.

The successful emergence of BPVs motivated a group of individuals adopting the moniker of Homo photosyntheticus. This movement aimed to introduce chloroplasts—the cell structures that facilitate photosynthesis found in plants—into their bodies to create energy through light exposure. The inspiration for this quest came from fascinating organisms like the solar-powered sea slug, which incorporates chloroplasts from algae into its own cellular framework.

Although the sea slug has evolved adaptations to maintain chloroplast function, it still requires continual replenishment of these organelles. The slug boasts a leaf-shaped structure, maximizing its surface area, but the potential energy contribution from photosynthesis is limited. For humans, the quest for self-sustaining energy through chloroplast integration, while symbolic, would yield only marginal returns due to our evolutionary biology.

Despite the biological limitations, members of H. photosyntheticus proudly embraced their commitment to renewable energy, often tattooing chloroplast designs as a testament to their ecological pledge to use electricity sourced exclusively from photosynthesis, ensuring a stance against fossil fuel dependency.