Some of them did go big on solar. BP Solar was a major solar manufacturer and subsidiary of British Petroleum (now just "BP"): https://en.wikipedia.org/wiki/BP

Some of them did go big on solar. BP Solar was a major solar manufacturer and subsidiary of British Petroleum (now just "BP"): https://en.wikipedia.org/wiki/BP_Solar https://en.wikipedia.org/wiki/BP_Solar ARCO Solar was another significant solar player in the 1980s: https://en.wikipedia.org/wiki/ARCO#ARCO_Solar https://en.wikipedia.org/wiki/ARCO#ARCO_Solar The first American solar company to target terrestrial applications, Solarex, was acquired by Amoco in 1983: https://cleantechnica.com/2014/10/24/sun-horizon-history-solar-pv-industry-look-ahead/ https://cleantechnica.com/2014/10/24/sun-horizon-history-sol... France's major oil company Total acquired a majority share of SunPower in 2011: https://store.globaldata.com/report/total-to-acquire-60-stake-in-sunpower/ https://store.globaldata.com/report/total-to-acquire-60-stak... There are a few reasons I can see why the oil companies never became "energy companies" with an equal emphasis on renewables: - The required competencies for success in manufacturing renewable energy equipment are very different from those required for discovering/extracting/refining oil. The production side of renewables is high volume manufacturing. The oil companies aren't going to do any better than existing big manufacturers like Siemens, Panasonic, or General Electric (to say nothing of more specialized manufacturers focusing only on renewable energy components). - The competition is fierce. Most of the world's top solar manufacturers from 15 years ago are now shut down, acquired, or have a tiny market share compared to the past. It would have taken a very lucky guess or the fortitude to endure years of losses for an oil company to keep an acquired solar company running consistently. - Renewable energy costs are falling every decade, and fierce competition (see previous point) means that prices have to fall also. This is very different from oil where global prices go up as often as they go down. Going all-in on renewable energy means betting on a future of high volumes and lower margins. That may look lucrative for a company starting from nothing, but for an oil company it's a very Kodak film-versus-digital kind of institutional shift.