I did a build where I really saw the positive effect of solar. I teched up to electric furnaces and replaced all of the coal driven ones with electric, includin

I did a build where I really saw the positive effect of solar. I teched up to electric furnaces and replaced all of the coal driven ones with electric, including efficiency modules, powered by solar. The steam engines became used only for brown-out protection. As soon as I did that the biter attacks became much more manageable and I could easily wall in with hardly any resistence. This was on death world. So I wouldn't say the mechanic doesn't work, for me it made a lot of sense.