Scientific Methodology
Computed, Not Claimed.
Every number on this platform traces to measured field data, published crop science constants, live market prices, or satellite imagery from the European Space Agency. Nothing is estimated, assumed, or adjusted without disclosure.
How We Calculate Trial Nitrogen
When you set up a trial, the platform calculates how much nitrogen to reduce on the treatment strip. This is the “Trial N” — the amount of synthetic nitrogen allocated to the strip where EL-I Tech's biological product is applied.
Trial N = max(Standard N − Soil Reduction, Minimum Floor)
Standard N is the farmer's normal application rate. Soil Reduction accounts for indigenous nitrogen release by soil type.
Soil-Type Reductions
| Soil Type | Reduction | Reasoning |
|---|---|---|
| Sandy | −100 kg/ha | Releases more indigenous N |
| Loam | −80 kg/ha | Standard retention |
| Clay | −60 kg/ha | High retention — less replacement needed |
Minimum Floors
| Crop Type | Floor | Why |
|---|---|---|
| Most crops | 10 kg/ha | Ensures biology can function |
| Soya & legumes | 0 kg/ha | Already fix N symbiotically |
Example:
A farmer using 210 kg/ha of standard nitrogen on loam soil:
Trial N = max(210 − 80, 10) = 130 kg/ha
How We Prove Nitrogen Contribution
This is the core scientific engine. After harvest, Calculator B processes yield data from both the treatment strip (with EL-I Tech product) and the control strip (standard practice) to quantify exactly how much nitrogen the biological product contributed.
Step 1: Moisture Adjustment
Raw yield measurements are adjusted to standard moisture content so comparisons are fair regardless of when or how the grain was weighed.
Adjusted Yield = Measured Yield × (100 − Measured Moisture%) / (100 − Standard Moisture%)
Step 2: Yield Comparison
Yield Increase (kg/ha) = Treatment Yield − Control Yield Yield Increase (%) = (Yield Increase / Control Yield) × 100
Step 3: Nitrogen Harvested
Converts the harvested grain into the amount of nitrogen it contains. The relationship between protein content and nitrogen is a well-established agronomic constant.
N Harvested (kg/ha) = Adjusted Yield × Protein Fraction / Jones Factor
Jones Factor defaults to 6.25 for most crops, except wheat (5.70) which has a different amino acid profile.
| Crop | Protein | Jones Factor | Standard Moisture |
|---|---|---|---|
| Maize | 8.9% | 6.25 | 12.5% |
| Wheat | 11.5% | 5.70 | 12.5% |
| Soya | 40.0% | 6.25 | 13.0% |
| Canola | 23.0% | 6.25 | 8.5% |
| Sunflower | 17.0% | 6.25 | 9.0% |
| Barley | 10.5% | 6.25 | 13.0% |
Step 4: EL-I Tech N Contribution
This is the number that proves biological nitrogen fixation works. It isolates the nitrogen that can only have come from EL-I Tech's product by subtracting everything else.
Soil N Implied = Control N Harvested − Standard N Input Expected Trial N = Trial N Input + Soil N Implied EL-I Tech N Contribution = max(0, Trial N Harvested − Expected Trial N)
In plain English:
We calculate how much nitrogen the soil naturally provides (from the control strip), then calculate how much the treatment strip should have harvested if it only had reduced synthetic N plus that same soil contribution. Any nitrogen above that expected amount is attributed to EL-I Tech's biological fixation.
The max(0, ...) ensures we never claim a negative contribution.
Financial Impact
N Reduction = Standard N − Trial N (kg/ha) Input Savings = N Reduction × N Fertiliser Price per kg Output Gain = Yield Increase × Crop Price per kg Combined Benefit = Input Savings + Output Gain Control Gross Margin = (Control Yield × Crop Price) − (Standard N × N Price) Trial Gross Margin = (Trial Yield × Crop Price) − (Trial N × N Price) Profit Increase (%) = (Combined Benefit / Control Gross Margin) × 100
This is how the 15–75% revenue uplift per product line is calculated. Each trial's profit increase is computed individually from its own yield data and local commodity prices on the day of harvest.
Where We Get Crop Prices
Live commodity prices are fetched daily at 06:00 UTC from two sources:
Crop Prices
Commodities-API — CBOT futures prices for wheat, maize, soybean, and canola in USD/tonne.
Exchange Rates
Frankfurter.dev (ECB data) — USD to ZAR, CAD, AUD, NZD.
| Crop | Conversion | Standard |
|---|---|---|
| Maize | 39.368 bu/tonne | 56 lb/bushel |
| Soybean | 36.744 bu/tonne | 60 lb/bushel |
| Wheat | Direct per tonne | — |
| Canola | Direct per tonne | — |
| Sunflower | 95% of soybean price | No direct futures contract |
Nitrogen fertiliser pricing: UAN-32 (Urea Ammonium Nitrate, 32% N content). Price per kg of pure N = UAN price per tonne / (1000 × 0.32).
How We Monitor From Space
The platform uses Sentinel-2 L2A satellite imagery (European Space Agency, free and open data, 10m resolution, 5-day revisit cycle) to track eight vegetation indices.
Biomass & Growth
| Index | Formula | What It Measures |
|---|---|---|
| NDVI | (NIR − Red) / (NIR + Red) | Vegetation vigour and biomass |
| EVI | 2.5 × (NIR − Red) / (NIR + 6×Red − 7.5×Blue + 1) | Enhanced biomass — reduces atmospheric noise |
| LAI | max(0, min(8, 3.618 × EVI − 0.118)) | Leaf area per ground area |
Chlorophyll & Nitrogen
| Index | Formula | What It Measures |
|---|---|---|
| CIre | (RedEdge3 / RedEdge1) − 1 | Canopy chlorophyll and leaf nitrogen |
| CIgreen | (RedEdge3 / Green) − 1 | Total chlorophyll via green reflectance |
| NDRE | (NIR − RedEdge1) / (NIR + RedEdge1) | Red-edge NDVI — more sensitive at high biomass |
Water & Moisture
| Index | Formula | What It Measures |
|---|---|---|
| NDWI | (NIR − SWIR) / (NIR + SWIR) | Vegetation water content |
| NDMI | (NIR − SWIR) / (NIR + SWIR) | Canopy moisture stress |
Unit Conversions
The platform automatically converts between metric and imperial based on your region.
| Measurement | Metric | Imperial | Factor |
|---|---|---|---|
| Area | 1 hectare | 2.471 acres | × 2.47105 |
| Weight | 1 kg | 2.205 lbs | × 2.20462 |
| Yield | 1 kg/ha | 0.892 bu/acre | × 0.892179 (maize) |
South Africa, Canada, Australia, and New Zealand use metric. United States uses imperial.
Source of Truth
All crop constants are maintained from EL-I Tech's Protocol Backend, authored by Gerhard Vermaak (Chief Scientist). Calculator B's methodology — particularly the N Contribution formula — is the scientific foundation of the platform, isolating biological nitrogen fixation from all other factors using standard agronomic principles.
Explore the trial results