UFS-2 Experiment (Apr - May 2014)
The second Unified Field Study (UFS-2) was performed from April to May 2014.
The overall objective of the second Unified Field Study (UFS-2) was to generate a robust inter-testbed dataset in algal biomass and lipid productivity and yield for the algal strain Nannochloropsis oceanica KA32 as a function of different regional, and environmental conditions among sites by controlling non-geographical-related variables including production systems, production process and protocols, system scale, and algae strain. In UFS-3 we compared the effect on productivity of three harvests per week with multiple dilution rates vs. one harvest per week with one dilution rate using both algal strains.
A total of 6 x 1,000 L (nominal volume at 25 cm depth) identical raceway pond simulators, paddle wheels, and data logging (e.g., YSI 5200 monitoring and control system with probes for pH, temperature, oxidative reduction potential (ORP), dissolved oxygen, conductivity/salinity probes, and a PAR sensor connected to one YSI unit) have been installed at each site. The six ponds allow experiments to be conducted in duplicate for up to three experimental variables in a simultaneous, randomized design. To date, we have run treatments in triplicate; however our data indicates that ponds of the same treatment have low enough variation that duplicates are sufficient for each treatment, which allows us to test more treatments at one time. In addition to the outdoor cultivation system harmonization, we have installed at each site an identical system for cultivation of indoor seed culture. This coupled with consistent cultivation management will allow for uniform production of starting culture across the sites in terms of volume of seed available and quality.
This experiment was initiated on April 3, 2014. For all data generated in this experiment, the ExperimentID is APR032014 .
Here is the experimental protocol used to conduct these runs. NOTE - UFS-2 was originally referred to as "UFS Spring 2014". There are several references to this earlier name in the protocol.
Pond Operational Data
Click here for the complete operational data for each pond at each site. These data include the measured pond depth (cm), pH, salinity, pond water temperature (C), nitrogen concentration (ppm as N), phosphorus concentration (ppm as P), N:P ratio (molar), the sample ID and tracking ID of a physical sample (if taken), the algae concentration (g/L) as dry weight and ash-free dry weight (AFDW), the ash content of the algal biomass (%), and the optical density at 750nm (OD750). Not all data are available for all sites and ponds.
Click here for the complete and daily-averaged instrumentation data for each pond at each site. These data include the pH, oxidation-reduction potention (ORP, mv), pond water temperature (C), pond conductivity (ms.cm), dissolved oxygen concentration (DO, mg/L), dissolved oxygen saturation (%), salinity (g/L), and photosynthetically active radiation (PAR, umol/m2/s). The PAR sensor was connected to only one of the ponds. Not all data are available for all sites and ponds.
Click here for the complete and daily-averaged weather data. These data include air temperature (C), relative humidity (%RH), Global Light Intensity (W/m2/s), daily precipitation (cm), wind speed (km/hr), and wind direction (degrees). Not all data are available for all sites.
Summary Harvest Data
Click here for the complete harvest data for each pond at each site. These data include date, strain, batch and source ID, pond treatment and depth (cm). The harvest data includes harvest number and time between harvests, harvest volume (L), amount (g), ash-free dry weight (AFDW; g/L) at the time of harvest, and an indication of a pond crash.
Compositional Analysis Data
Click here for the complete compositional analysis data for each of the point harvests at each site. The data include the lipid (FAMELipids.AF), protein (Protein.AF) and carbohydrate (Carbohydrates.AF) content of biomass harvested from the ponds throughout the cultivation experiment and immediately freeze-dried. All data were collected using standardized methodology (http://www.nrel.gov/bioenergy/microalgae-analysis.html) by each of the participating laboratories. Data collection included the implementation of QA/QC in analytical methodologies; a standard data collection spreadsheet and a method validation standard material (Nannochloropsis granulata), a biomass sample that is in abundance and has been well characterized in all labs through an interlaboratory round robin validation. Samples (1-4 L) for biochemical analysis during the production runs were collected from the ponds within +60 min of sunrise and concentrated to a pellet by centrifugation, freeze dried, and stored until the conclusion of the experiment. The biomass samples were split into experimental sets of 15-20 samples and each set included triplicate samples of the QC biomass. All data presented here are averaged over technical replicates and expressed as percent (%) on an ash-free dry weight basis of harvested biomass. The link with productivity data in other data sets found on this site can be made through the tracking identifier (Tracking ID). Some data points are missing due to either data not meeting the rigorous QC requirements or experimental errors during data collection. "