We do not need to account for energy use in sustainable biology based systems.
We receive energy in plenty freely from the sun on our planet. It is dispersed in wind, evapotranspiration, heat, plant growth… and generally comes to equilibrium (though that is in question now over the long term). The earth receives all the energy we need for free and we give nothing back in exchange, therefore we don’t need to account for renewable energy use.
On the other hand we have finite resources on this planet that are required for life to multiply. We do want to multiply life on the planet (not necessarily human and livestock) as this is the best place to put the excess out of balance CO2, collecting in the atmosphere, into a vibrant and more massive biosphere.
The limiting resource is then not energy, but minerals for life. Obviously also water. So I feel sustainability accounting needs to focus on accounting for minerals-in minerals-out as a package. Sustainable cities receiving minerals in the form of food, fiber , wood… need to adapt to clean and refine a package of the same amount of mineral to send out to grow more. Two points here: “minerals for life” are not simply the 16 required for plant growth, but all of those required for healthy creatures or soil.
When cities take in product and send it out in equal proportion and in immediately farm or forest usable form, we have become sustainable in our cities no matter how much energy we use or don’t use.
BTW, it is up to the cities to send it out clean and usable, without toxins and heavy metal contamination.
Minerals of life accounting.