It's not easy being green, but the digital exam sector is often quick to cheer-lead environmental virtues versus paper. But are digital exams really green? Do we have the full picture?
Isn’t digital computing all green energy? The International Energy Agency claim global data centres consume 200 TWh of electricity annually, or 1.5% of global electricity use - much of it for cooling, and still mostly from non-renewable sources.
Manufacturing a computer is surprisingly intensive. The average PC and 17-inch monitor requires at least 240 kg of fossil fuels, 22 kg of chemicals (including heavy metals such as mercury, cadmium, and beryllium oxide), and 1.5 tonnes of water. Almost 2 tonnes of materials for 2 pieces of equipment weighing 25 kgs in total.
Surely paper is easier to recycle than computers? It seems that way. Print is tried and trusted, and chemicals used in print production have become safer, although not immune to incidents. The Environmental Paper Network claims the energy to make recycled paper is a third-less than virgin paper fibre.
Recycling computers involves testing, cleaning, and refurbishing all by hand, down to the last threaded screw. Batteries are always recycled separately. Intriguingly, a ton of circuit boards contains 40 to 800 times more gold than a ton of extracted ore.
Has anyone tried to benchmark paper versus digital exams? There’s surprisingly very little research, although two recent case studies have tried.
Case Study 1 AQA In October 2023, England school exam owner AQA published a life cycle study for paper versus digital, using the 2022 English Language GCSE as a reference. It considered analogue inputs of the exam paper, inner and outer packaging, transport, scanning, storage, and destruction.
AQA assumed an average lifespan of 5 years per computing device. For digital, a reduction of 9% in the amount of carbon emitted per exam was calculated.
Case Study 2 NEBOSHÂ Professional international health and safety exam owner NEBOSH published a study in August 2020. Over 8,000 learners in 94 countries across 911 venues took an on-screen exam. NEBOSH calculated that digital delivery saved 331k air miles and 150 tonnes of CO2, which normally would have taken over 74k trees a year to absorb. This is based on learners not travelling to test centres, and not sending air freighting exam paper packets. Digital delivery also saved 162k sheets of paper, or around 19 trees.
Would new, lower-power computers be greener? To further reduce environmental impact, why not use machines assembled in Britain, such as the Raspberry Pi? The Pi draws 5V DC and 10-15W, compared to 170W for PCs. The price point and total cost of ownership for the Pi versus laptops and PCs is eye-opening. England’s Department of Education IT service and digital equipment guidance for schools specifies that local servers must meet the Energy Star mark for energy efficiency. A good match for the Pi’s capabilities, and for delivering on-screen off-line GCSEs serving a LAN network.
So digital exams aren’t totally ‘green’ yet? More data is needed. We don't have the full picture. Exam authoring, production, learner and invigilator travel, and standardisation activity all need to be fed into future modelling. Despite high-stakes digital exams being delivered for over three-decades, the environmental evidence and use cases are only emerging.
Are we saving the planet by deploying digital exams, or just shifting the problem elsewhere?