Solar power is a safe alternative which can replace current fossil fuels like coal and gas for the generation of electricity that produces air, water, and land pollution.
Overview
Solar power is energy from sunlight that is converted into thermal or electrical energy using solar panels. Thermal solar panels are used for heating water only whereas Photovoltaic (PV) panels are for electricity generation as well as heating water.
Why should farmers consider solar power?
- Solar energy has zero greenhouse gas emissions and offers an alternative for fossil fuel energy thus providing an opportunity for climate change mitigation and pollution reduction.
- Excess electricity can be stored in a rechargeable battery for later use and batteries can also provide backup power in the event of blackouts.
The following video provides all the necessary information on electricity and heat generation using solar power.
What are the considerations for developing solar power?
- When choosing which panels to install the environment needs to be considered including how this will affect the output efficiency and performance of the panels over time
- Panel efficiency will differ depending on the type of panel that is chosen.
- European warranties both on inverters and panels are an essential consideration when choosing which supplier to choose and which system to install.
Economic and Environmental Benefits
The economic benefits from using a solar PV system for a typical 84-cow herd dairy farm are summarised in Table 11. Solar is a renewable source of energy that produces fewer emissions than fossil-based energy sources.
Table 11 The economic benefits of solar PV system
| Scenario 1 | Scenario 2 | |
| 40KW solar power with batteries | Without grant | With grant |
| Life span(years) | 20 | 20 |
| Initial capital cost() | 54350 | 38045 |
| Annual savings | 12599 | 12599 |
| Return on Investment(%) | 23 | 33 |
| Payback (years) | 4.3 | 3.0 |
The grant covers 30% of the initial cost
84 cow herd
Research
Research at Farm Zero C
At FZC, a renewable energy plan is being implemented by Watt footprint. The holistic approach combines solar energy and wind turbines with storage batteries and efficient use of electrical energy at the farm. The system design/size and limiting factors have been identified as follows:
- In order to accurately determine the daily peak loads a targeted sub-metering system is essential to not just identify the significant energy users but also the actual load profile of these. This will allow for measured peak demands to be understood and waste within operations reduced, increasing the return on the solar PV system.
- The MIC (Maximum import capacity) associated with the site will be a limiting factor to the size of the system that can be installed on the inverter size. A MIC of 29 has been taken for the purposes of this study.
- The area of the roof will also be a limiting factor for installation size, however, most farmers will have sufficient roof space available for the proposed system size. An area of 320sqm has been chosen for the purposes of this study.
- A system oriented towards east-west would suit the profile of the site due to separate peaks across the day. Generation would be spread and utilised better.
- Based on the assumed daily unit price for solar energy of €0.20c/kWh and night rate of €0.13c/kWh and peaks during milking times, battery storage would be a viable option, in this case, to act as a buffer between usage and generation.
Other research
Key findings from previous research are as follows:
- Solar energy is the most cost-effective renewable source of energy and the standalone solar systems are the most practical currently in Ireland as farmers would not be able to inject excess electricity into the grid.
- Using a case study of a farm with 100 spring-calving herd, Teagasc, (2021)researchers showed that if a 6Kwp, is installed for such a farm, 30% of electricity would end up being provided by a renewable source thus offsetting 2.4 tonnes of CO2 per year.
Links to more research
Regulations
The following regulations, policy documents and actions apply to solar energy on farms.
The White Paper: Ireland’s Transition to a Low Carbon Energy Future 2015-2030
Draft Renewable Electricity Policy and Development Framework (2016)
AgClimatise roadmap– The use of solar energy contributes to action 18 of the roadmap to climate-neutral agriculture.
“Action 18: Generate at least a 20% reduction in agricultural energy use by 2030 across all farms. In addition, generate at least 20% deployment of renewable energy technologies focusing primarily on energy-intensive farming systems”
Available support
Grant aid for energy efficiency projects falls under the Sustainable Energy Authority of Ireland (SEAI). There are a number of funds and support that are available, however, solar is not fundable as a single measure and must be part of a holistic approach to energy efficiency upgrades.
Better Energies Community grant (BEC)
Targeted Agriculture Modernisation Schemes (TAMS)
Suppliers
Some of the suppliers of solar systems are listed below.