Robots and shocks: emerging non-herbicide weed control options for vegetable and arable cropping

Figures & data

Table 1. Estimated energy requirement ranges of selected selective and broadacre weeding methods.

Weeding Method	Low Energy Estimate MJ ha^−1	High Energy Estimate MJ ha^−1
Selective (Site Specific)
Pulsed microshocks^1	0.25
Pulsed electric^2	4.5
Herbicides – site specific^3	15
Electrocution – site specific^3	15	19
Hoeing – site specific^3	17
Laser pyrolysis – site specific^3	15	249
Broadacre (Whole field)
Flextine harrow^3	4	6
Spoon weeder^3	10	11
Herbicide^4	38	115
Herbicide including chemical manufacture^3	46	712
Herbicide including chemical manufacture^5	47	1,007
Laser pyrolysis^6	100	900
Electrocution^7	32	77
Power harrow^8	230	384
Hot water^3	1,500	7,600
Hot water^9	3,840	19,150
Microwave^10, 11	9,600 ^10	75,000 ^11

¹ Bloomer et al. (2022)

² Blasco et al. (2002)

³ Coleman et al. (2019)

⁴ Kaufman and Schaffner (1982); Audsley (2000)

⁵ Calculated from Audsley (2000), Helsel and Pimentel (2007) and Alluvione et al. (2011)

⁶ Estimated from Wöltjen et al. (2008), Coleman et al. (2021) and Carbon Robotics (2023)

⁷ Kaufman and Schaffner (1982)

⁸ Calculated from Barber (2010)

⁹ Estimated from Martelloni et al. (2021)

¹⁰ Brodie (2012)

¹¹ Calculated from Wayland et al. (1975), Helsel and Pimentel (2007) and Alluvione et al. (2011)

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