Since there are no currently active contests, we have switched Climate CoLab to read-only mode.
Learn more at
Skip navigation

Please find below the judging results for your proposal.

Finalist Evaluation

Judges'' comments

Semi-Finalist Evaluation

Judges'' ratings


Judges'' comments

Judge 1:
It is not clear how much funding would be required for commercializing the proposed process. How far is the company from commercial-scale operation (what scale?) and how would the funds be used? What is the overall energy balance? A more realistic description of the impact is necessary--statements such as "It makes cheaper air travel without pollution possible at last" are terribly naive.

Judge 2:
The approach to reducing the climate impacts through alternative fuels made from renewable sources is surely an interesting and promising one. It’s a common approach and it is well analyzed - and recognized in political decision making (see e.g. carbon credits in aviation’s CORSIA scheme). This leads me to 2 main issues with this proposal: (1) We know from analysis that the lifecycle climate impacts of alternative fuel sources strongly depends on the production process. In the proposal, I have not been able to find an analysis which shows how well the fuel performs in terms of CO2 output “well-to-wheel/wing”. This is important to address. Otherwise, the actual environmental benefit is not fully proven. (2) Since biofuel incentives are already created in many policies, there is scope to introduce efficient pathways for alternative fuel production. As such, the industry will develop the most promising biofuel technologies. This is an ongoing optimization effort, which will take time. As such, the proposed idea might be amazing to move things forward in the optimization, but the novelty of the alternative fuel approach for reducing the carbon footprint of transportation is somewhat limited. I highly encourage the authors to go on with their business idea and wish them good luck.

Judge 3:
The proposal seems interesting and it certainly can have significant potential for use of lignocellulose material. I wish the authors included more technical information on the process, and how they derive the economics. Also, since the products are in aquous solutions, it is unclear if the dewatering effort was factored in.

Share conversation: Share via:

Mark Cox

Nov 26, 2017


1 |
Share via:

I did not get to this before the Nov 6 deadline but here are the responses anyway:

Judge 1: The company is installing its first commercial scale reactor this coming year. They are closing on a plant that currently has offtake agreements for 8 million gallons a year of cellulosic ethanol. They are currently raising money, about $30 million, to complete this phase. Part of the funds will be used to acquire the site and the remainder on refitting equipment and the start of employment of a team to operate the plant. For each pound of lignocellulosic feedstock less than half a kilowatt hour is required to complete one cycle of the ball mill. So for 100 lbs of raw material entering the system only 45 kiloWatt hours of electricity is required amounting to an input cost of about $9 for 100 lbs. I'm all too well aware it sounds naive, but in this case all the "naivete" (and the judge actually is saying that its too great a claim to make) is backed up by hard facts. If the final cost of a gallon of aviation fuel is indeed around $1.50, then saying "cheaper air travel without pollution" is by no means beyond credibility.

Judge 2: Normally CO2 reductions for various biofuels are disappointingly low. Initially the ethanol industry was plagued with "well to wheels" analyses that showed that there was no CO2 reduction or that the energy balance was greater making ethanol than just leaving it to diesel or gasoline. After some years the farmers dispelled that intial doubt by improving their systems but as they matured it became clear that they were about 48% - 49%. DOI: 10.1111/j.1530-9290.2008.00105.x

Cellulosic ethanol has long been believed to offer reductions of over 80% and this form of cellulosic is deemed to have a greater than 95% reduction in CO2. You are correct in saying that the incentives especially in the US, where D3 RIN credits of over $3.00 per gallon means that at a cost of $0.90 per gallon and a sales price of $1.50, revenues per gallon would be $4.50 for a cost of $0.90 and profit of $3.60 per gallon. This is quite an attractive incentive and all other methods of cellulosic ethanol production are having problems whose costs are eating this advantage up.

Judge 3: The lignocellulosic material is shredded or chipped and added to the contents of a ball mill which already contains kaolinite clay as a catalyst and the required ball bearings. The system is sealed and spun at a specific RPM for just 12 minutes until a carefully calculated 80% conversion rate has been achieved. The mill is opened and water is added to dissolve the sugars. The lignin floats and is taken off with a foaming agent, while the unconverted remaining material falls to the bottom along with the non sacrificial clay catalyst. All parts are cycled back to the start except for the sweetened water and the unconverted remains of the first batch are the first to convert in the second batch. The sweeted water is directly fermented to ethanol or any of myriads of other products.To this point, the 0.45 kWh per lb of lignocellulosic material is the only energy input and this can come from economic night time power or renewable energy. Use of steam at only 0.07lbs per lb, increases the efficiency of the conversion. Cellulose is non soluble and the hydrolysed version with separated sugars and lignin, is soluble in water. Only enough water is added to dissolve the sugars that are there for an optimum fermentation solution. Water administration is a very closely attended to aspect of the process and nothing is wasted, and much is recycled from the distillation and other parts of the process to the start again. Dewatering is very much factored in. In fact, it was discovered that just making sugar syrup used so much evaporation energy that this part of the process was dropped in favor of simply adding the front end as a module to any ethanol distillation plant, avoiding the water recovery issue from selling syrup or granular sugars.