“Daddy, is garbage bad?”
My 5-year old daughter is entering first grade in about a month. Her questions about all things in life have become a bit more complex in the past year, but I can usually still come up with a satisfactory answer in short time – but this one left me thinking for a bit.
Of course she was probably asking the question because I had just snapped a photo of our garbage can. After returning from 5 days at the University of South Florida in the BioWET (Biological Waste to Energy Technology) class, I will never look at a can of garbage the same again. That orange peel at the bottom of the can…would the world be a better place if I put it through the garbage disposal down the drain to the wastewater treatment plant? My local wastewater utility anaerobically digests their sludge and uses all of their biogas for process heat, building heat, and a chiller system – seems like a good option, right? I also know that our garbage winds up in a waste-to-energy facility, so at least it’s being incinerated and converted to power which is certainly not the worst case scenario. But where does that process line up with other options for processing my orange peel through biological processes to produce energy?
Compared to my daughter, my 4-year old son’s typical line of questioning can generally be described as rapid fire.
Liam: Why are you taking a picture of the garbage can?
Me: So I can post it to the BioWET blog.
Me: Because Dr. Yeh compelled each of us to post our reflections of the class online.
Me: Because we all came into our class with different perspectives and we’re trying to capture some of our impressions and findings from the week and share those with others.
Me: Eat your Cheerios.
My daughter can explain to you that the water that goes down the drain winds up in pipes “under the house” and eventually goes under the street and then winds up at the wastewater treatment plant. I’m sure there are a lot of adults that couldn’t get that far if asked about their sanitation system. So her question about garbage being bad maybe isn’t too surprising. She knows what gets recycled and what goes in the garbage. She knows our Christmas tree gets picked up in January and ground into mulch which winds up on our flower beds in the spring. But…is garbage bad? Good question. That depends on a lot of things. What happens to your garbage? Does it go to a landfill? Is that landfill properly designed and operated? Does it capture biogas and is that biogas then used to produce heat or electricity? Or is it flared? Does your garbage go to an incinerator? Does that incinerator capture the heat to produce energy? So many questions. So many nuances.
I didn’t walk away from the week at USF with global experts, energetic graduate students, and other researchers with a clear answer, but I don’t think that was the point. What I did walk away with was an impression that we have many options on how to optimize our recovery of energy from organic waste. And the details of those options are being researched by a lot of very smart people. The paradigm shift of thinking of waste not as waste, but as a resource is gradually happening. It starts with forward-thinking engineers and scientists who can harness natural processes to recover resources for an increasingly resource-constrained world. But that shift is implemented when policy-makers, leaders, and the public get behind the concept. There are many technical challenges ahead of us. We will continue to optimize and look for new pathways to energy generation. The good news is that we already know how to get there. But, widespread adoption of this path forward will require non-technical barriers to be overcome. I am optimistic we’ll get there and my grandkids will never ask their mom or dad “is garbage bad?” because by then they’ll know that there really is no waste – only resources waiting to be converted into something useful.
University of South Florida