Don't produce cheapest items, trade for them on the market for more expensive items. As of this writing vegetables are so cheap in relation to other items that it does not make economical sense to produce them, because market gives us such a good trading prices. So, in respect to the energy per produce it makes sense to produce items with have high(est) trading value and trade them for vegetables.
It also makes sense to build second production facility for item of highest market demand and keep producing those items and trade them for the ones you need.
to finalize, I would not produce veggies iron and clay at current market condition, but I would double produce meat.
This strategy saves me energy on production of cheap goods.
Energy management is one of the main aspect of the game, expecially in the beginning and i personally rely on some of the strategy suggested (example, do not produce vegatables but acquire em on the market)
Thanks for your sharing!