Solar PV Feasibility Study for a Dairy Farm in Somerset

Introduction and Project Overview

The objective of this project is to renovate an old dairy farm located in Yeovil, Somerset, in order to take advantage of cost reductions offered by renewable energy. The UK government has encouraged the use of renewable energy by introducing the FIT (Feed-in Tariff) subsidy for solar power across the country. In recent years, carbon emissions have increased as a result of conventional electricity use and methane from cattle waste. Renewable energy resources have been identified as effective power sources for reducing carbon emissions on farms. This project intends to exploit the benefits of renewable energy resources to renovate and retrofit the old dairy farm, and will carry out a cost-benefit analysis of different renewable energy options to identify the most suitable choice.

The project evaluates three renewable energy technologies — solar photovoltaic (PV), solar thermal, and wind energy — to identify the option that will produce maximum benefits, including reducing the farm's carbon footprint, lowering operating costs, and increasing net revenues.

Project Structure

The project is structured as follows. Section 1 discusses the storyline and baseline project scenario, including the project location with relevant images and maps, and the assumptions underpinning the energy baseline. Section 2 assesses the renewable energy resources using a systematic approach to narrow down the renewable energy potential at Yeovil, Somerset, and discusses the appropriate tools, techniques, and methods for project implementation. Section 3 assesses the feasibility of the selected renewable energy technology using financial techniques such as cash flow analysis, internal rate of return, annual carbon savings, energy analysis, and pictorial elements. Section 4 provides a critical reflection on the feasibility assessment, addressing the strengths and weaknesses of the project approach, the quality of information collected, and the validity of the findings. Section 5 presents conclusions and recommendations, summarising the overall project and identifying avenues for future improvement.

Project Assumptions

After consulting with project stakeholders, the following specifications and assumptions were established:

The economic feasibility of the project is based on a budget of £11,000. The interest rate is 4.15%. The chosen renewable energy technology must be both economically and sustainably feasible. The project will evaluate a combination of the following renewable energy resources: solar PV, solar thermal, and wind energy.

Project Location and Baseline Scenario

The project concerns a 250-acre dairy farm located in Yeovil, Somerset. The farm produces fresh cow milk and fermented cow milk. The farm owners are committed to protecting the environment from carbon emissions, both for present and future generations. Over the years, the farm has relied on conventional electricity as its primary energy source; however, this increases carbon emissions and is not cost-effective for farm operations. Additionally, the quantities of methane produced by the cattle contribute to the daily carbon footprint. The farm therefore intends to comply with environmental legislation by reducing its carbon footprint through an effective renovation and retrofit — switching from conventional electricity to renewable energy resources. The renovation is also necessary to assist in reducing climate change and pollution (Courtney, 2012).

Yeovil is a small town located in the southern part of Somerset, England. It has a population of approximately 45,000 and is situated 210 kilometres from London. The town has an annual mean temperature of approximately 10°C (50°F) with diurnal variation. January is the coldest month, with a mean temperature of between 1°C and 2°C, while July and August are the warmest months, with a daily mean temperature of approximately 22°C. These climatic conditions are favourable for dairy farming production (Ekoogen, 2010).

Carbon emissions in Yeovil stand at 2.3 tonnes per person, owing to the combination of fuel mix and housing stock. This level of carbon emission in Somerset reinforces the need for a sustainable energy choice for the dairy farm. Renewable energy technology has been identified as an effective strategy for reducing these emissions. Furthermore, the wide landmass available in Yeovil provides a suitable physical environment to support the dairy farm's operations and the installation of renewable energy systems.

Assessment of Renewable Energy Technologies

This section identifies and evaluates potential renewable energy technologies for the dairy farm by assessing the environmental and economic feasibility of solar thermal, solar PV, and wind energy. The feasibility analysis includes technical suitability and environmental impact, both of which influence the selection of the most appropriate technology.

Solar PV

Photovoltaic (PV) panels use semiconductors to convert solar radiation into direct current electricity. PV panels can be installed on flat rooftops or on the ground. One key benefit of solar PV is that the panels generate electricity during daylight hours, which can be used directly on the farm. This offsets electricity costs and reduces the overall cost of farm operations. Since solar radiation is freely available, a 50 kW array would reduce the farm's reliance on conventional energy and minimise the depletion of natural resources. Solar energy can also be collected via electronic devices such as solar cells.

The cost of solar PV in 2014 was £2,229 per kW, declining to £1,971 per kW by March 2015, reflecting a consistent year-on-year downward trend. Over the past ten years, the price of solar PV has fallen by approximately 40% annually (DECC, 2015). Table 1 below summarises the costs of solar PV panels per kW between 2014 and 2015 in the UK.

Table 1: Solar PV Costs per kW Installed (2014–2015)

2014 – April: Median £2,079 | Mean £2,229
2014 – May: Median £2,050 | Mean £2,193
2014 – June: Median £1,998 | Mean £2,141
2014 – July: Median £2,000 | Mean £2,117
2014 – August: Median £2,000 | Mean £2,103
2014 – September: Median £1,931 | Mean £2,056
2014 – October: Median £1,958 | Mean £2,057
2014 – November: Median £1,875 | Mean £2,004
2014 – December: Median £1,834 | Mean £1,982
2015 – January: Median £1,923 | Mean £2,012
2015 – February: Median £1,901 | Mean £1,979
2015 – March: Median £1,834 | Mean £1,971
Total 2014/15: Median £1,949 | Mean £2,070

Wind Power

Wind power uses turbines to generate electricity. Large-scale wind capacity can range from 1.97 MW to 7.5 MW, sufficient to produce approximately 18 GWh of electricity — enough to supply around 5,000 three-person households. Small-scale wind systems, generating up to 100 kW, are effective for farms, homes, businesses, and telecommunication sites, and can be installed on building rooftops. Approximately 60% of onshore farms in the UK use wind power to generate electricity, and the cost of wind power has fallen from around $108 per megawatt hour to $85, making it increasingly cost-competitive.

Despite these benefits, wind power has notable limitations. It is intermittent by nature, depending entirely on wind speed and availability. Wind turbines can also generate noise pollution, although recent technological advances have produced quieter blade designs — albeit at greater expense. Furthermore, wind turbines pose a threat to wildlife; they can kill protected bird species, which could expose the farm to violations of environmental legislation (Kraemer, Hu, Muto, Chen, et al., 2008).

Solar Thermal

Solar thermal systems capture heat for water heating and building heating purposes. The process of converting solar energy to heat is more than twice as efficient as solar PV conversion. However, solar thermal technology faces significant constraints in terms of availability, and may not provide energy in a form suitable for all dairy farm requirements. On balance, analysis of the three technologies reveals that solar PV is the best choice for this dairy farm, given its availability, cost efficiency, and sustainable performance (Akhigbe, Belaief, Gursoy, 2011).

References

Akhigbe, I., Belaief, C., & Gursoy, O. Y., et al. (2011). Feasibility study of renewable energy sources at the Emerson Plant in Ithaca, NY.

Courtney, H. (2012). Decision-driven scenarios for assessing four levels of uncertainty. Strategy & Leadership, 31(1), 14–22.

DECC. (2015). Official statistics: Solar PV cost data. Department of Energy & Climate Change, United Kingdom.

Ekoogen. (2010). Yeovil economic profile. South Somerset, United Kingdom.

Kraemer, D., Hu, L., Muto, A., & Chen, X., et al. (2008). Photovoltaic-thermoelectric hybrid systems: A general optimization methodology. Applied Physics Letters, 92(24).