Howard T. Odum’s (controversial) concept of ‘emergy’ attempts a comprehensive accounting of the energy consumed in direct and indirect contributions to make a product or service. Emergy allows for extremely slow and vast processes to be acknowledged as vital contributions to life, which we can no longer take for granted in an age of accelerating technological advances. Solar energy emerges as central in energy modelling, responsible for most of the sources of energy we rely upon today, including wind, tides, and, fossil fuels.

Some areas of the world get more sunlight than others, some ‘use’ more sunlight than others. In Europe, we are able to use considerably more energy than we receive naturally from the sun through imports in various concentrated forms, principally petroleum, coal and natural gas. According to The World Bank Group’s Global Solar Atlas, Brussels is one of the least sunny cities in Europe, receiving only 3 kWh/m2 on an average day, and only 1000 kWh/m2 a year. Yet Brussels’ energy consumption is comparable to that of most European cities.

Solar Share coins are made of PET plastic, a petroleum bi-product that constitutes ancient sunlight concentrated in organic material over millions of years. A few grams of PET have the same embodied energy as a square metre of yearly solar irradiation in Brussels.

How might our understanding of economics change if the instruments we used for money had an equivalent value to the solar energy required to materially produce them? As a speculative response, each Solar Share coin embodies the average solar irradiation received at a specific urban location.

Solar Share – The Coins, (2020), DISNOVATION.ORG & Baruch Gottlieb, installation, plexiglass frames, coins made of plastic waste (Precious Plastic, PET)