Hall Donnell runs an intensive dairy unit in partnership with his parents, Derick and Sylvia, on 200 acres outside Ballymagorry, a small village in northwest Co Tyrone.

While there is a firm focus on driving output per cow and hectare farmed, the ethos is on doing this in an environmentally sustainable way.

Over the past nine years, Hall has been harnessing solar energy to power the farm, reducing his reliance on electricity coming from the national power grid.

Hall Donnell aims to make his farm self-sufficient in terms of power and water.

There have been additional investments and other innovations that reduce the cost of running the farm. These include heating water by recirculating gas from refrigeration condensers.

Slurry is applied using a trailing shoe tanker on the grazing block. Such is the efficiency of recycled nutrients, the 50ac grazing platform only received 27 units/acre of CAN in 2021. This year, the plan is to reduce this to zero.

Hall is also planning to install new solar panels this year with batteries able to store unused power generated in daytime for use during the evening and night.

Ultimately, Hall’s plan is to make the farm as self-sufficient as possible.

Herd details

The farm carries 110 Holstein cows yielding 10,050 litres last year on a 340-day lactation. Cows consume 2.6t of concentrate, giving a yield from forage of 3,017 litres at 4.05% butterfat and 3.15% protein.

Over the past four years, cows are milked through two GEA robots.

Cows are milked three times per day through two robots. The energy needs of the robots suit the power supply on farm.

Since the robots were installed, yields have increased by 1,000 litres/annum. Cows calve on a flat profile from September to May as this fits best with the robot setup.

Breeding

Replacement rate is around 30% with heifers mated to sexed semen, along with 20 to 30 of the top-performing cows.

Thereafter, conventional beef semen is used on cows and an Angus stock bull acts as a sweeper. All heat detection is carried out through the robots.

Milk solids is an area that is now being targeted for improvement. Hall aims to take cows to an average yield of 12,000 litres and lift butterfat and protein by 0.2%.

Grazing

Unlike many high-yielding dairy herds on robotic milking systems in Northern Ireland, cows are allowed to graze.

The 50ac grazing block is split into a morning and evening grazing set up across 14 paddocks. Cows access grass from the shed using an automated grazing gate.

The grazing platform is split between day and night paddocks. To the left, cows go to night grazing. To the right, cows go to day paddocks.

The gate will not release a cow from the shed that has not been milked prior to the morning or evening grazing allocation.

Fertiliser

Slurry is the dominant nutrient source on the farm and is applied to the grazing block every six weeks at a rate of 2,000 gallons/acre using the trailing shoe.

The grazing platform is 50ac across 14 paddocks.

While the aim is to spread zero chemical N on the grazing platform this year, the silage ground will get 50 units/acre for each cut along with 3,000 gallons/acre.

Silage is made on a dedicated two-cut system of high-quality forage for milk cows.

Slurry is the main fertiliser used on farm. The grazing block gets 2,000 gallons/acre every six weeks.

A smaller third cut is produced without slurry and targeted to dry cows.

Surplus grass on the grazing platform is also baled.

Moving to self-sufficient energy

Hall first installed 20kW solar panels on a south-facing shed roof in 2013 at a cost of £29,000.

This investment was repaid in four years with the help of renewable obligation certificates (ROCs), a Government incentive to encourage uptake of green energy generation.

The farm and dwelling house now use 99% of electricity generated on farm.

The net electricity costs purchased for the farm was £900 last year.

The decision to install robotic milking machines was mainly down to their compatibility with renewable energy generated on the farm.

Robots have a steady power demand over a 24-hour period with cows milked three times a day. Another aspect the robots offered is greater efficiency in terms of running costs.

For example, the vacuum pump with the robot runs at 10% of the rotation speed of the vacuum previously used to run the old parlour.

Before the switch to robots, the farm exported £1,000/year worth of renewable electricity back to the grid as less power was being utilised inside the farm gate.

Cows are allowed to access grass using a grazing gate.

Storing power

This year will see the installation of 30kW panels and storage cells, making the farm and dwelling house completely self-sufficient in terms of electricity.

While the initial outlay has yet to be finalised, the process is at an advanced stage. Given the surge in energy costs, this would shorten the repayment period for Hall.

Refrigeration gas is recirculated to pre-heat water for use in the dairy and dwelling house. From April to early autumn, all hot water used in the dwelling house is generated on the farm without the need for central heating.

Lights in the main cubicle shed have been replaced with LED units, which operate off timers and a photocell that determines when lighting needs to be turned on.

This controls internal lighting for cow comfort and complies with Red Tractor assurance scheme requirements for dairy farms.

Bore well

For Hall, the final piece in the jigsaw would be to install a bore well on the farm to supply all water requirements. He has been exploring this avenue for a couple of years now and hopes to progress with it inside the next year.

If this comes to fruition, the farm will be able to operate off grid in terms of energy and water.

Herd plans

There are no plans to increase the herd size. The main cubicle shed has space for 130 milking cows. Investment has been made in recent years to expand housing for dry cows and heifers.

Rather than look to increase output through additional cows, Hall reckons it would be more profitable for his herd to focus on driving milk yield per cow.

Given the growing focus on carbon and emissions, lifting yield would dilute the amount of carbon per litre of milk.

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