When pursuing a sustainable lifestyle it is practically essential to consider getting around organic waste. Organic waste cannot properly biodegrade in landfill because the conditions are not correct for it to do so, instead it becomes even more damaging to the environment because it releases methane, a greenhouse gas 84 times more potent than carbon dioxide. In an ideal world we would all have access to free community composting services (which will hopefully be the future) and/or would be composting ourselves, but as someone who's grown up in a city where your average family lives in 484 square feet, I will be the first to admit that currently composting is not a wide-spread option. However, as I always say, sustainability is not black and white, and there are other ways to make sustainable use out of your organic waste before it goes to landfill - or for us lucky ones in the compost bin. One of my favourite ways to do this is through veggie scrap stock.
Making your own vegetable stock has a multitude of benefits. On the sustainable end of things you avoid any packaging waste by not buying a pre-made vegetable stock (i.e. in a tetrapak) and by hopefully buying most of your produce package free, you make as much use as possible of organic waste, and if your pre-made stock is from overseas you avoid food miles. You also have full control over the ingredients added, and potentially skip out on unhealthy and unnecessary chemicals in pre-packaged ones which are not only damaging to your body but also to our environment.
The process itself is pretty simple; save all your veggie scraps in a container in the freezer, once it's full put them into a large pot with water and simmer for a few hours or until it's reached your desired taste. Take out all the scraps so you are left with the stock and separate it into various containers to freeze; when it's needed in a recipe simply take it out, defrost it, and viola! I recommend freezing them in one cup measurements and/or as tablespoons in ice-cube trays. It's incredibly simple, cost effective, saves energy and time, is environmentally friendly, and tastes super yum so I hope you enjoy!
(P.S. alex's pro tip: add vegemite or marmite to the stock whilst it simmers for a lil extra kick)