With cheap natural gas from fracking and little by the way of state funding, the use of anaerobic digestion to process food waste in the US has yet to become mainstream. However, a number of states have introduced bans on the landfilling of yard trimming and garden waste, and others including California, Massachusetts, Rhode Island and Vermont have also banned food waste from landfill.
In theory this should bode well for the anaerobic digestion industry, but so far even in most of those states implementing such bans a glut of new AD plants has failed to materialise. In Massachusetts, which banned any establishment that creates 1 ton (907kg) or more of food waste per week from sending any to landfill, by July 2015 just four of the 49 sites accepting diverted food waste were anaerobic digestion plants – and one of those was a pilot facility.
“There’s definitely a drive to tackle food waste in the United States and Canada,” explains Ashwani Kumar, vice president of engineering at Anaerobic Digestion facility developer and operator, Harvest Power, Inc. “They’re trying to find the right policy frameworks to make it happen and some of the states are close to getting it right.”
“It’s very different to Europe. For a start the US has a huge landmass. On top of that there is no requirement of nutrient management, organic compost is readily available, electric power is very cheap, and also the only push is for diversion from landfill - and for that there are alternate routes where the food can go. It can go to animal feed or compost,” he tells WMW.
“For these kind of projects there are also really high expectations. Not just for the technology, but also very high financial expectations,” Kumar continues. “For developers there are so many thing to go through, the permitting the land acquisition, the feedstock contracts, the off-take contract. It’s a very difficult market where you need very experienced local developers.”
Fairy Tale in Florida
However, in addition to sites in Canada, Massachusetts based Harvest Power has been successful in developing its Central Florida Energy Garden project, which processes some 120,000 tons (109,000 tonnes) of organic wastes annually while and produces 5.4 MW of energy. The facility helps businesses and communities across central Florida recycle organic material. The plant’s first customer was the Walt Disney World Resort, which is also located within the Reedy Creek Improvement District.
To encourage more local businesses to divert their waste away from landfill and the company embarked on its ‘Orlando Or Landfill? Responsible Food Recovery’ campaign which challenged consumers to ‘Choose Orlando’.
“The Florida plant came about because the local district was already collecting organics and composting them, but the composting was causing a nuisance with odour and birds being attracted by the decaying food,” explains Kumar. “For composting you need to have the right carbon to nitrogen ratios and if you don’t get it right and you have too much food waste in the feedstock it smells.”
Having already developed a food waste AD project in London, Ontario Harvest approached the district with its proposal to treat the food waste separately.
“It worked for us because it was a site where 60-70% of the feedstock was contracted with a very strong district for 10-20 years. The price for the electricity was fixed for the next 10 years and the investors were happy with these arrangements – there was very little risk from a finance point of view,” notes Kumar.
“The developers were happy because they could get land very close to the wastewater treatment plant and they could the feedstock to the plant easily. It was a win-win situation,” he adds.
Chicken and Egg
Harvest Power’s Florida Energy Garden is a great example of how a successful AD food waste plant should be developed. Each interested party plays their part and the pieces of the jigsaw all slot together. But if you take one of those pieces away, you can never complete the jigsaw.
One of the major stumbling blocks currently for would be developers in many states is that without the treatment capacity there is no incentive to for separate food waste collections. Without the feedstock being collected it is very hard to convince financiers to stump up the not insignificant funds necessary to develop the capacity.
But there are North American examples which state policy makers should look to when assessing the best approach.
“Canada is very progressive,” says Kumar. “In Ontario they adopted the German approach of feed-in-tariffs and became a leader in Canada. Then 20 or 30 of these projects came up very quickly and it reached a situation where feedstock became scarce.”
“The plants were actually competing with each other for feedstock and the gate fee started dropping,” he continues. “But the policy framework is changing as they’re learning about it, so it’s no longer an open feed-in-tariff.”
California Dreaming
As with many aspects of waste management in the US, California is blazing a trail when it comes to facilitating the development anaerobic digestion plants. It offers numerous grant programs through state and regional agencies which can be used towards the cost of construction and equipment.
Waste and recycling firm CR&R Environmental Services has taken advantage of such funding in the development of huge facility in the City of Perris. Currently under construction the plant is being built in four phases each of 83,000 ton. Work on phase one, an 83,000 ton (75,300 tonne) per year plant, has been completed. According to the developer once all four phases are complete the facility will be the largest of its type in the world.
CR&R’s partnership with the City of Perris on this megaproject is far from being a one off, and has recently been bolstered by new legislation. In October last year California Governor Jerry Brown signed two environmental bills that will increase recycling of food waste and other organic materials.
Of the two, AB 876, authored by Assembly Member Kevin McCarty requires local governments to plan for the building of sufficient composting and anaerobic digestion infrastructure to process the organic waste generated in their jurisdictions over the next 15 years.
"California’s local governments have done a great job ensuring sufficient disposal capacity for their residents, but, as increasing amounts of discards are instead managed at recycling facilities, it is time that we apply the same forethought to planning for the infrastructure that will be necessary to handle this material,” comments Nick Lapis, Legislative Coordinator for Californians Against Waste Lapis.
It’s certainly not a situation which has passed Harvest Power by. According to Kumar the company has been focusing a lot of effort on the state, and is confident that it is well placed to work with Californian communities as they seek to develop the infrastructure needed to meet the new legislation.
Reasons to be Cheerful?
Although the widespread adoption of AD to treat food waste in the US may be happening more slowly than some would like, there is plenty to be optimistic about.
“From a technology point of view there are a lot of developments in the US,” says Kumar. “There are some good companies that have come through locally and improved the technology, especially on gas upgrading, so yes there is a big technology push here.
“At the end of the day what I’ve learned is that he adds.
“Yes it looks good, but getting into the granularity of it there is still a lot of work that needs to go in - but there is a lot of potential, everyone sees that. It’s just a matter of getting the formula right for how the policy, the finance and developers can all come together to make it work,” Kumar concludes.
