For those asking "Why bother? The energy usage is tiny".
https://energy-efficient-products.ec.europa.eu/product-list/smartphones-and-tablets_en#consumers-1
Mobile phones and tablets produced under these rules will save almost 14 terawatt hours in primary energy each year by 2030. This is one third of the primary energy consumption of these products today. The new rules will also help to optimise the use and recycling of critical raw materials.
In 2030, the savings on EU27 acquisition costs are € 20 billion, which combined with € 0.6 bn lower energy costs and € 0.8 bn additional repair costs, leads to € 19.8 billion (22%) expense savings (€ 98 per household).
So basically, by promoting energy efficient and repairable devices, the plan is to save €20bn annually in savings and not to generate 14TWh of electic power across the EU. That power saving is about the annual output of a single nuclear reactor. (1.6GW x 24h x 365.25d = 14TWh)