Today, the Digest goes in-depth with the world’s most unique farming system, cultivating a direct petroleum substitute as a crop.
In New Mexico, Sapphire Energy announced that the first phase of its Green Crude Farm, the world’s first commercial demonstration algae-to-energy facility, is now operational in Columbus.
Construction of this first phase, which began on June 1, 2011, was completed on time and on budget.
When all phases are completed, the facility will produce 1.5 million gallons per year of crude oil and consist of approximately 300 acres of algae cultivation ponds and processing facilities. The farm has already produced 81 tons of algae biomass to date.
The Sapphire Energy and algae biofuels backstory
It’s been a few years now since the company was founded, so for those newer to the dark arts of algae biofuels, let’s recap the basics. Algae is grown, in the Sapphire system, photosynthetically in open ponds (utilizing a “raceway” design) – that is, in brackish water and using CO2 and sunlight.
Algae also needs a source, in the water, for some nutrient requirements that can include nitrogen, potassium, phosphorus, and iron – unlike terrestrial plants, that absorb them from the soil).
Now, why isn’t algae covering the oceans, if all it needs is water, CO2 and sunlight? Well, algae can blow through the available nutrients, and can be subject to pests, predators and being out-competed for nutrients.
Sapphire was founded in 2007 to address these challenges – to create an industrial system for feasibly growing and harvesting drop-in algae biofuels. Investors include Arch Venture Partners; The Wellcome Trust; Cascade Investment, an investment holding company owned by Bill Gates; and Venrock, the venture capital arm of the Rockefeller family. Along the way, its picked up support from the DOE, and USDA.
The labs are based in SanDiego as is the company. However, the pilot facility is in Las Cruces and the Green Crude Farm is in Columbus, both in southern New Mexico.
Why algae? It’s promise in terms of cost and scale – second, because that’s what, at the end of the day, the original fossil petroleum reserves were made of, giving confidence on a performance basis as a drop-in substitute requiring no infrastructure change.
Pond size and operations
The cultivation area consists of some of the largest algae ponds ever built with groupings of 1.1 acre and 2.2 acre ponds which are 1/8 of a mile long. The initial phase also includes all the necessary mechanical and processing equipment needed to harvest and extract algae and recycle water for the 300 acre Green Crude Farm.
Sapphire is now conducting all united operations, including cultivation, harvest and extraction in a continuous process
In March, the first seeding of ponds with algae, otherwise known as inoculation, took place and a series of “shakedown” tests began to ensure that all systems are working as planned.
Today, Sapphire reports that farming operations are exceeding Sapphire Energy’s internal productivity goals in terms of biomass yield, demonstrating that large scale cultivation is possible and much larger cultivation systems can be implemented with the proper agronomic processes in place. The company harvested its first crop in June without any system difficulties.
Next, the Green Crude Farm is preparing to transition its operations to a winter variety of algae while continuous cultivation, harvest and extraction activities continue.
Sapphire Energy partnered with AMEC Project Engineering, who coordinated with 16 New Mexico-based contractors, to complete the first phase of the Green Crude Farm during 12 months of active construction.
The harvesting solution
Sapphire is using a widely-used system called Dissolved air flotation (DAF) – used extensively in water treatment to remove suspended matter such as oil or solids. The removal is achieved by dissolving air in the water or wastewater under pressure and then releasing the air at atmospheric pressure in a flotation tank or basin. The released air forms tiny bubbles which adhere to the suspended matter causing the suspended matter to float to the surface of the water where it may then be removed by a skimming device.
Sapphire Energy will continue to conduct “shakedown” testing, as well as operate and expand farming operations over the winter, as the facility is commissioned into 2013. By the end of 2014, the Green Crude Farm will produce 100 barrels of Green Crude per day. The commercial demonstration project is expected to prove “commercial” techno-economics, and Sapphire’s commercial scale Green Crude facility
Financing and job creation
The $135 million Green Crude Farm, also known as an Integrated Algal Bio-Refinery, was funded with both private and public funds, including $85 million in private investment from Sapphire Energy backed by a USDA loan guarantee and a $50 million grant from the US DOE.
634 full-time equivalent employees were hired throughout the entire construction phase, and $16 million was directly invested with local New Mexico contractors.
To date, Sapphire has not discussed specifics of the system economics – except to confirm that its target continues to be parity with crude oil.
“Bringing our Green Crude Farm online is not only an important accomplishment for Sapphire Energy, but a critical step toward a viable alternative energy future,” says Cynthia ‘CJ’ Warner, CEO and chairman of Sapphire Energy. “What was once a concept is now becoming a reality and model for growing algae to make a renewable crude oil for energy.”
Sapphire operations: above-ground oil field, or farm?
Well, both. It’s a farm, whose crop is a direct substitute for petroleum (hence, Green Crude Farm).
Perhaps the best way to understand Sapphire, for those new to the craft, is to to begin with the idea of a rice paddy.
In a rice paddy, one floods the field, seeds it; grows biomass using photosynthesis, defends it against pests, weeds and predators; harvests, separating the desired material (in the case of rice, threshing the edible rice from the plant); and then processes the extracted material into higher-value products.
There are four significant differences.
First of all, scale. Algae are teency, one-celled organisms. That creates a different class of predators, pests and weeds that, themselves, can be microscopic or otherwise have novel features to defend against. Scale also changes the way in which extraction (that is, separating the oil fraction from the protein and carbs) is accomplished.
Second, algae are not anchored to the soil. Combined with their microscopic scale, that leads to significantly different harvesting operations.
Third, growth rate. Rice yields 4-10 tonnes per hectare per year. At 25 grams per square meter per day with a 25 percent lipid content — recently described as “table stakes” by Tony Haymet, director of the Scripps Institution of Oceanography at UCSD — algae biomass yields are in the 91 tonnes per hectare per year range, with around 23 tonnes of crude oil produced per hectare per year.
That translates to around 3200 gallons per acre per year. (Note, Sapphire has not been reporting specific growth rates in the lab or in the field – these are figures used for illustration)
Fourth, continuous harvest. Unlike a traditional terrestrial food crop, where you get one shot on goal per year – and look at the US drought to tell us everything we need to know about the risks thereof – with algae, you get multiple shots, because algae – as a one-celled system, grows by cellular division, and you can be in continuous harvest, pulling out excess biomass and leaving the rest in the pond to continue to divide and redivide.
In this way, the Green Crude Farm has something in common with modern hay operations, where you get repeated harvests throughout the season.
But think of the similarities, not just the differences. Note, for example how Sapphire relates its story in terms of a March seeding season, and a June initial harvest – and the seeding of winter algae later in the year. Algae, at scale, is shaping up in so many ways like a farming operation.
The Sapphire time-machine
The Sapphire challenge is not just to solve the particular new challenges in growing algae commercially, and solve them at a feasible cost, but to collapse the time frame that it took to address the challenges in these problems in, say, rice – down from, er, about 1,000 years into 10.
There’s not only a biotechnology challenge there, but ultimately an engineering challenge – how to make a system for growing algae that can produce a green crude competitive with fossil crude not only in performance, but in cost.
The controversy over drop-in hydrocarbon algal fuels these days is one of cost, since the performance has now been established (for example, in aviation and military testing) and there is no infrastructure change required with the fuels that Sapphire aims to produce. (Other groups that aim to produce algae biodiesel, will share the blending and infrastructure challenges associated with all biodiesel fuel).
So, the next step in the Sapphire system is to verify that, once operations are fully established, that the technology is meeting its cost goals. We’ll find out from Sapphire in the future what scale they propose to operate at commercially, per farm.
In that case, Sapphire will be balancing the advantages of size (economies of scale) against its disadvantages (availability of sufficient water and affordable CO2).
The Green Crude Farm — in pictures
The Green Crude Farm — before construction
The Green Crude Farm — in construction
The Green Crude Farm — today
The Green Crude Farm — in video
Algae biomass in harvest in via Sapphire’s Dissolved Air Flotation (DAF) system.
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