Calculates emissions due to energy required to deliver water to the measured crop.
Overview
Irrigation infrastructure emissions are calculated on fields that are irrigated. Otherwise the emissions value for this activity will be zero.
Irrigation infrastructure includes energy required to deliver water to the plant and piping/metal/etc. but not the water emissions itself from the soil. Emissions are calculated from the amount of water used to produce the measured crop given an irrigation method.
Limitations
In the case that defaults (via Monitor) are used to assess Irrigation status, it determines if the field is irrigated or not. It does not have any idea if irrigation was used for that specific season during the production of that crop. So, in the case that Regrow is defaulting irrigation data there is a chance the field emissions are over estimated and give emissions for irrigation when irrigation may not have actually been turned on for that crop/season.
Regrow has chosen to use Ecoinvent emissions factor for Tier 1 at a market level. This provides EFs per country. Each country has a mix of irrigation methods (ex. drip irrigation, sprinkler, etc) commonly used in that region. Likewise there is no opportunity for the user to specify a more specific irrigation method today. This is a possible area for expansion in future versions of Regrow.
All irrigation events are accounted for in our emissions calculations; however, these emissions are only attributed to the main commodity crop, not secondary or cover crops. This is likely to be an unusual situation. This is important because yield is a component of the emissions calculations and only the measured crop's yield will be used in the calculation, even if irrigation was also used on a cover crop.
User Inputs
For each measurement there are inputs required. In the case that the user cannot provide the inputs then Regrow will default them according to our Tier Definitions (see that article for more information).
|
Inputs |
Description |
Unit/Options |
|---|---|---|
|
Crop |
The name of your measured crop. This should be a single crop per measurement. If a cover crop is included in the cultivation cycle of the measured crop, then it will be included in the emissions attributed to the measured crop. |
See our list of supported crops |
|
Harvested yield |
The harvested fresh yield for your measured crop, before any drying or other losses might occur. This is used as the yield denominator. |
kg per hectare |
|
Location |
The area used in the production of your measured crop. This should be a single field or single managed unit. Location is used to inform the emissions factors used. In most cases this is a global value for the crop and some select crops x geography this is country-specific. |
Country-level or field level |
|
Irrigated Y/N |
You have two options for providing irrigation status of a field: 1. entering it directly or 2. using Monitor (in regions available) to default. When Monitor is used to provide irrigation status Regrow will give an irrigated Yes or No status per field location.
|
Field level |
|
Irrigation rate |
The amount of water provided to the measured crop. |
m3 / kg of yield |
|
Irrigation method |
Today this input is always defaulted. For each region, a representative mix of irrigation methods are automatically provided with the emissions per country. Irrigation method gives the type of system used to provide that water to the crop. Each type provides a different level of efficiency (considering both conveyance and use by crop) as defined by Ecoinvent:
|
Surface, Drip, Sprinkler |
Irrigation rate
The irrigation rate assumed is per crop per country, only if the field is irrigated and no user-provided primary data is available.
Using source: Pfister, S., Bayer, P., Koehler, A., & Hellweg, S. (2011). Environmental impacts of water use in global crop production: hotspots and trade-offs with land use. Environmental science & technology, 45(13), 5761-5768. https://doi.org/10.1021/es1041755 there are both high and low rate values. This assessment assumes the high values as a more conservative approach.
Irrigation energy emissions coefficients by irrigation method
All emission sourced from Ecoinvent 3.11v. The assume energy involved is a mix of electricity and diesel. This is factored into the emission coefficient and cannot be edited by the user.
Ecoinvent's market data also gives a representative breakout of irrigation method per region.
Drip irrigation: “Drip irrigation is mainly applied in intensive cultivations planted in rows (vegetables, fruit trees, melons, bananas, papayas, flowers, grapes, etc.).
It is not recommended for potatoes, salad leafy vegetables, groundnuts, alfalfa and other dense planted crops.”
Surface irrigation: “Surface irrigation is the application of water by gravity flow to the surface of the field. This application can be either the entire field is flooded (basin irrigation) or the water is fed into small channels (furrows) or strips of land (borders).
Only the surface irrigation excludes infrastructure as in this case water flows by gravity.”
Sprinkler irrigation: “Sprinkler irrigation is a method of applying irrigation water similar to natural rainfall. Water is distributed through a system of pipes usually by pumping. It is then sprayed into the air through sprinklers so that it breaks up into small water drops which fall to the ground.
This method is suited for most row, field and tree crops and water can be sprayed over or under the crop.”