Judge energy technology across its whole industrial life

What are solar panels made from, and how environmentally friendly is their manufacture?

It depends on the design; manufacturing impact has to be weighed against efficiency, service life, disposal, and the emissions displaced during operation.

Solar-panel materials vary by design, so the useful comparison is whole-life environmental cost. Some highly efficient panels may be relatively damaging to manufacture, yet their long service life and energy output can offset that initial burden. The same caution applies to batteries and to the specialised concrete used in power stations: production impact cannot be judged without asking how long the product lasts and what it replaces. Concrete technology has changed rapidly, and prefabrication and lower-carbon mixes can reduce emissions while retaining durability. Life-cycle assessment is more informative than labelling a technology green or ungreen from one stage of its production.