Farmers are expected to be able to sell their solar power back to the national grid under the Clean Energy Guarantee, which will pay farmers between 14c and 20c/unit of electricity.

Farmers who obtain solar PV panels under the new Targeted Agricultural Modernisation Schemes (TAMS), will also be able to sell power to the grid.

It is expected that farmers obtaining solar panels under TAMS will be limited to the size for self consumption, this is about 25,000kWh for a 100-cow herd.

Solar power

Speaking at the Irish Grassland Association (IGA) Dairy Conference in Co. Cork today (Wednesday, January 18), Dr. John Upton from Teagasc, Moorepark stated that he expects farmers to be able to sell power back to the grid.

But he noted that currently the upgrade required to the lines in order to supply this power to the grid, would be the responsibility of the farmer.

Dr. John Upton

Upton also noted that there is a significant cost difference between bought-in energy compared to energy sold to the grid.He instead suggested that farmers store or use this energy on farms.

Dr. Upton noted that the peak time for energy requirements on farms does not match the peak time that solar panels are generating energy. This means that in order to maximise the use of this energy on farms, some storage is needed.

But he questioned the potential payback of battery storage and instead suggested that farmers use this energy to heat water.

Speaking to Agriland, Dr. Upton said: “A water heater is a no brainer you can get a 30KW water heater to use/store the extra energy.”

Energy usage

Dr. Upton also outlined strategies to reduce energy consumption on dairy farms during his presentation at the IGA conference.

He highlighted research conducted by Teagasc into the areas of highest energy demand on farms.

This research determined that milk cooling accounted for 31% of energy demand; water heating (23%); milking (20%); other (18%); water pump (8%); and lighting 3%.

Dr. Upton said that due to the introduction of chlorine-free detergents, the demand for hot water has increased, which has likely slightly increased its contribution further.

He said that at the current cost of energy, on average, this is costing €12/1,000L of milk sold, noting that this ranged from €7.50 to €14/1,000L of milk sold.

He suggested that farmers ensure their plate cooler is working efficiently as possible, as over 80% of farms have a plate cooler.

He said that the goal of a plate cooler is to reduce the milk to within 5° of the incoming water, e.g., if the water is 10°, the aim is to reduce the milk temperature to 15°.

He also stated that it is important to ensure that enough water is going through the plate cooler; the milk-to-water ratio needs to be 1:2. Used correctly, it will reduce milk cooling energy requirements by up to 40%.

He also suggested that farmers look at some of the new schemes that will be released in 2023 for solar PV panels.