Thank you for the opportunity to help you with your question!
Eco-efficency is the process of determining lower cost resources in term of natural capital that can replace high cost resources. For instance, on an individual level; one person might be using plastic bags to carry his or her groceries, that individual could replace those plastic bags with a cardboard bag that could be reusable. Therefore, less natural capital is used to produce a unneeded product.
On a business scale, a company could enforce regulation within the store in regards to eco-efficency. For instance, some companies have mandated that each level of a floor install recycle bins. These bins would then be emptied to the proper facilities. This process alone, could be massive in terms of eco-efficency considering the large amount of material waste produced that can be recycled.
Please let me know if you need any clarification. I'm always happy to answer your questions.