Wasted Energy: Converting Discarded Food into Biofuels

Diverting just a portion of the world's food waste to waste-to-energy systems could free up large amounts of landfill space while powering vehicles and heating homes.

CHEW ON THIS: Diverting even just a portion of the world's food waste to energy could put a significant dent in our collective carbon footprint.

Food waste is indeed an untapped resource with great potential for generating energy. Some one third of all food produced around the world gets discarded uneaten, and environmentalists, energy analysts and entrepreneurs are beginning to take notice. Diverting even just a portion of this waste to so-called waste-to-energy (WTE) systems could free up large amounts of landfill space while powering our vehicles and heating our homes, and thus putting a significant dent in our collective carbon footprint. Perhaps that’s why WTE is one of the fastest growing segments of the world’s quickly diversifying energy sector.

Currently there are some 800 industrial-scale WTE plants in more than three dozen countries around the world, and likely thousands of smaller systems at individual sites. Most employ anaerobic digesters, which make use of microorganisms to break down and convert organic waste into a fuel such as biogas, biodiesel or ethanol. With some 70 percent of food waste around the world still going into landfills, there is a lot of potential feedstock to keep this environmentally friendly carbon neutral fuel source coming.

“Waste-to-energy doesn’t involve drilling, fracking, or mining, and it doesn’t rely on scarce and politically-charged resources like oil,” reports RWL Water Group, an international company that installs water, wastewater and waste-to-energy systems. The waste from small slaughterhouses, breweries, dairy farms and coffee shops can power hundreds of typical homes each day if the infrastructure is in place to sort, collect and process the flow of organic material.

Navigant Research, which produced the 2012 report “Waste-to-Energy Technology Markets, which analyzes the global market opportunity for WTE, expects waste-to-energy to grow from its current market size of $6.2 billion to $29.2 billion by 2022. “With many countries facing dramatic population growth, rapid urbanization, rising levels of affluence, and resource scarcity, waste-to-energy is re-establishing itself as an attractive technology option to promote low carbon growth in the crowded renewable energy landscape,” says Navigant’s Mackinnon Lawrence. “China is already in the midst of scaling up capacity, and growth there is expected to shift the center of the WTE universe away from Europe to Asia Pacific.”

The question is whether governments and individuals will make the effort to support diversion of waste into yet another separate stream. In areas where such systems are working, individuals are incentivized to separate out their organic and food waste because it saves them money on their trash pick-up bills. And bakeries, restaurants, farms, grocers and other big producers of organic or food waste provide an endless source of feedstock for WTE systems as well.

“We’re barely scratching the surface of this potential—dumping over 70 percent of the world’s food waste into landfills, rather than harnessing it for fuel and electricity,” reports RWL. “Over the next 25 years, global energy demand will grow by 50 percent, while global oil supply dwindles at a rapid pace. Waste-to-energy is an obvious solution to meet the world’s burgeoning energy demand.”

http://www.scientificamerican.com/article.cfm?id=food-waste-to-energy

Up to Two-Fifths of Fruit and Veg Crop is Wasted Because it is 'Ugly'

Produce that does not meet retailer standards in UK is fed to animals or ploughed back into ground, according to study.

The report also found the average household threw away more than 5kg of food a week. Photograph: Chris Radburn/PA

Up to two-fifths of a crop of fruit or vegetables can be wasted because it is "ugly", a report on food waste has shown. Produce grown in the UK that does not meet retailer standards on size or shape or is blemished is often used for animal feed or simply ploughed back into the ground even though it is edible, with as much as 40% of a crop rejected.

The report, commissioned by the UK's global food security program, also showed that the average household throws away more than 5kg (11lbs) of food a week, and nearly two-thirds of that waste is avoidable. The waste costs £480 a year per household on average, and £680 per family.

Households throw away a fifth of the food they buy, wasting it for reasons ranging from cooking and preparing too much food to not using it in time before it goes off, the study showed. Consumption and initial production are the areas where the majority of food is wasted in the UK, the study said. Retailers respond to demands by consumers for high-quality food by imposing standards that can lead to much of the crop being wasted, but some progress is being made with supermarkets marketing "odd shapes and sizes" for fruit and vegetables.

There is also growing evidence that more UK consumers are prepared to accept "ugly" fruit and vegetables, amid concerns over sustainability and increasing food prices, the research said. In developing countries, much of the loss of food occurs during post-harvesting storage, processing and packaging.

Tackling waste globally is a major part of the action needed to provide enough food to feed a growing world population sustainably and tackle hunger, which affects one in eight people worldwide, the report said.

Around a third of food produced globally is lost or wasted. Prof Tim Benton, an expert on Food Security at the University of Leeds, said: "Over 5 million people in the UK live in deep poverty, where basic food provision is a daily challenge.

"Nearly 400,000 people needed support from food banks last year, according to the Trussell Trust. "At the same time, 15m tons of food is wasted annually, with nearly half discarded within UK households. Reducing the scale of losses and waste throughout the entire food system is a crucial step towards improving global food security."

The report highlights priorities for research to help reduce food waste, including improving harvesting and packaging technologies, good seasonal weather prediction and new ways to reduce food waste within the home.