Biodiesel Feedstock Collected to Unplug London's Arteries

Conventional practice for restaurant oil and grease waste is generally one of two things: either hire a service to haul off and "manage" the grease bin contents; or, sneak it down the drain. We home cooks follow suit. In fact we're probablly far worse for the environment by our actions. We either smuggle grease and oil to the landfill, in a jar, or pour it down the drain directly. The local result of grease pouring is shown in the picture. At the sewerage plant, further downstream, oil skimming and grease trapping are a basic part of the public employee's job, paid for by taxpayers. The oil and grease entering the sewerage plant either gets burned, producing C02, or "digested" by the sewerage bugs, which also produces C02. No matter how much grease reclamation happens, all the animal grease and plant oil purchased as food ultimately ends up being biologically or chemically oxidized. If not by our own metabolism, it happens by chemical or bacterial breakdown in sewerage systems and surface waters. It's true that, back in the "old days", animal fat was purchased from homeowners and restaurants by soap making companies; but, ultimately, even soap making was just a useful diversion on the path to biodegradation...although a far better destiny than plugging sewers enroute.

Making biodiesel from waste oil and grease is all to the benefit of reduced sewerage system budgets, improved surface water quality, and more efficient, cleaner transportation. And, it's clear that our European friends are a leap ahead of the US in reaching those benefits. The Guardian of Nov. 2, 2005 typifies the progress with this headline: "A fat lot of good: Britain's much-maligned love of fried food could prove an unexpected aid to cutting traffic emissions and tackling blocked sewers." And so "the capital's restaurants and cafes are being encouraged not to dump their used cooking oil down the drain illegally but, instead, to offer it for free collection and reprocessing into biodiesel fuel".

These numbers tell the tale: "At the moment, about 15,000 tonnes of used cooking oil is collected every year from London's caterers. But the total available in the capital could be up to 37,000 tonnes a year. Capturing it all would require a massive effort. Realistically, the potential market for biodiesel in London is up to 25,000 tonnes a year, or 28m litres, says the report".

Here's a big picture challenge for TreeHuggers around the world. Lets focus on collecting all the waste oils we can instead of just cheering every new seed oil producing scheme or biodiesel plant being planned. If we only have so much time and personal energy for curbside collection, oil and grease markets offer an economic and a political incentive that probably exceed those for can and bottle collection. Ascendant markets will bring new allies and cooperation.