10. Battery fire safety must be taken seriously
Lithium-ion battery systems require proper design, installation and emergency planning.
Government guidance notes that lithium-ion storage presents a small but material fire risk and that this risk needs to be managed appropriately. GOV.UK
For planning applications involving lithium-ion battery storage of 1 MWh or more in England, government guidance encourages applicants to engage with the relevant fire and rescue service before submitting the application. GOV.UK
Farmers should consider:
- Battery location.
- Fire separation.
- Emergency access.
- Manufacturer requirements.
- Ventilation.
- Flood risk.
- Impact protection.
- Fire detection.
- Isolation arrangements.
- Insurer requirements.
A battery should never simply be placed wherever there happens to be spare space.
11. Wind power: Excellent on the right site, disappointing on the wrong one
Wind turbines can provide substantial renewable generation where wind resources are suitable.
Unlike solar, wind can generate at night and during winter.
This can potentially complement solar generation extremely well.
However, wind energy is highly site-dependent.
A turbine installed in a poor wind location may never achieve the output assumed in the sales quotation.
Important factors include:
- Average wind speed.
- Turbulence.
- Turbine height.
- Nearby trees.
- Buildings.
- Hills.
- Terrain.
- Grid availability.
- Planning constraints.
- Maintenance access.
The correct approach is to obtain reliable wind-resource information rather than relying solely on an installer saying:
“It is always windy around here.”
Local observation is useful, but investment decisions need better evidence.
12. Why turbine height matters
Wind closer to the ground experiences greater interference from buildings, vegetation and terrain.
Higher turbines may access stronger and more consistent airflow.
This is why a small turbine placed immediately behind a large farm building can perform poorly even though the surrounding area appears windy.
The location of the turbine can be as important as the turbine itself.
13. Wind maintenance can be underestimated
Solar panels contain no rotating blades.
Wind turbines do.
That means farmers should consider:
- Gearboxes.
- Bearings.
- Blades.
- Generators.
- Braking systems.
- Tower inspection.
- Electrical equipment.
- Specialist maintenance.
- Crane access.
Before purchasing a turbine, establish:
Who will maintain this machine in 10 or 15 years?
Also establish how quickly parts can be obtained if the manufacturer or installer disappears.
14. Small-scale hydro: Potentially one of the most dependable renewable resources
Farms with suitable rivers, streams, weirs or watercourses may have hydroelectric potential.
Hydropower can be particularly attractive because, where water flow is reliable, it may produce electricity continuously.
Solar may generate primarily during daylight.
Wind may vary hour by hour.
A suitable hydro resource may operate day and night.
But the site requirements are demanding.
Two fundamental characteristics determine hydro potential:
Head
The vertical fall in the water.
Flow
The quantity of water passing through the system.
A site with high flow but almost no drop may have limited potential.
A steep drop with insufficient flow may also produce little energy.
Both must be assessed.
15. Hydro requires environmental investigation
Using a watercourse is not simply an engineering question.
Projects may require consideration of:
- Water abstraction.
- Impoundment.
- Fish passage.
- Ecology.
- Flood risk.
- River flows.
- Protected habitats.
- Land ownership.
- Planning.
- Environment regulator permissions.
Farmers should establish the regulatory position before commissioning major civil engineering work.
Civil works such as channels, pipes, weirs and turbine houses may represent a significant part of project cost.
16. Biomass: Renewable energy based around heat
Biomass systems generally produce heat by burning fuels such as:
- Wood chips.
- Wood pellets.
- Logs.
- Other suitable biomass fuels.
They can be useful for farms with substantial heating requirements.
Possible applications include:
- Poultry buildings.
- Pig units.
- Workshops.
- Farmhouses.
- Offices.
- Hot water.
- Certain drying processes.
A biomass installation should be designed around genuine heat demand rather than around the idea of owning a renewable boiler.
17. Biomass fuel quality matters enormously
Two loads of woodchip can behave very differently.
Important characteristics include:
- Moisture content.
- Chip size.
- Contamination.
- Energy content.
- Storage conditions.
Wet fuel contains energy that must first be used evaporating water.
Poorly prepared fuel may also cause:
- Blockages.
- Incomplete combustion.
- Additional ash.
- Increased maintenance.
- Boiler shutdowns.
If a farm intends to produce its own wood fuel, harvesting, seasoning, drying, storage and handling must all be included in the economic calculation.
18. Do not base a new biomass investment on obsolete subsidy assumptions
This is particularly important.
The UK Non-Domestic Renewable Heat Incentive supported technologies including biomass, but the scheme is closed to new applicants. Existing accredited installations may continue to have obligations and payments under their existing arrangements. GOV.UK
Therefore, a salesperson presenting an old RHI-based return-on-investment calculation for a new project should immediately raise questions.
The current investment needs to stand on current energy savings, available incentives and realistic operating costs.
19. Solar thermal and heat pumps should not be forgotten
Renewable farm energy discussions often focus entirely on electricity.
But farms can also have substantial heat demand.
Solar thermal systems heat water rather than generating electricity.
Heat pumps move heat rather than creating it directly through combustion and can potentially be suitable for some farm buildings and processes.
Whether they are economically appropriate depends on:
- Required flow temperature.
- Building insulation.
- Heat demand.
- Electricity price.
- Existing heating system.
- Available heat source.
- Capital cost.
They should be assessed alongside biomass rather than automatically excluded from the discussion.
20. Anaerobic digestion deserves its own category
Although your forum description mentions biomass rather than biogas specifically, anaerobic digestion is highly relevant to farm renewable energy.
An anaerobic digester uses biological processes to break down organic material without oxygen.
Potential feedstocks can include:
- Slurry.
- Manure.
- Crop residues.
- Purpose-grown crops where appropriate.
- Food or organic wastes subject to regulation.
The resulting biogas can potentially be used for:
- Heat.
- Electricity.
- Combined heat and power.
- Biomethane production.
Digestate remains after digestion and can have agricultural nutrient value.
However, AD plants are complex businesses rather than simple pieces of farm machinery.
Feedstock supply, planning, environmental permitting, digestate handling, gas equipment and long-term maintenance must all be considered.
21. Renewable energy should not compete unnecessarily with food production
There is an important land-use question surrounding renewable energy.
Should highly productive agricultural land be removed from food production when roofs, yards, lower-grade land or dual-use systems could be available?
The answer differs between farms.
Government planning policy in England specifically recognises the importance of protecting high-quality agricultural land when
development proposals are assessed. GOV.UK
Solar development can sometimes coexist with agricultural activity.
Sheep grazing between solar arrays is one example.
There is also growing interest in agrivoltaics, where agricultural activity and electricity generation intentionally share land.
The correct design depends on the farming activity, machinery access, panel configuration and commercial arrangement.
22. Buying the system versus leasing the land or roof
Farmers may encounter several commercial models.
Farmer-owned
The farm purchases the renewable system.
Advantages can include:
- Ownership of the asset.
- Full benefit from electricity savings.
- Greater operational control.
Disadvantages include:
- Capital requirement.
- Financing risk.
- Maintenance responsibility.
Developer-owned
A third party installs and owns the equipment.
The farmer may receive:
- Roof rent.
- Land rent.
- Discounted electricity.
- A combination of payments.
The financial risk may be lower, but contractual commitments may last for decades.
Power Purchase Agreement
A developer installs or finances equipment and sells electricity to the farm under an agreed contract.
This may reduce initial capital requirements but requires careful review of:
- Electricity pricing.
- Inflation adjustments.
- Contract length.
- Minimum purchases.
- Maintenance.
- Termination rights.
- Property sale.
- Roof repairs.
Long contracts deserve professional legal review.
23. Never sign a 20- or 30-year renewable lease without understanding the end of it
Long-term renewable agreements may affect:
- Future farm sales.
- Mortgages.
- Land value.
- Tenancies.
- Succession.
- Development opportunities.
- Access rights.
Questions worth asking include:
- Who owns the panels?
- Who owns the cables?
- Who owns the battery?
- Who removes everything at the end?
- Who pays for removal?
- What happens if the operator becomes insolvent?
- Can the agreement be transferred?
- What happens if the farmer sells the land?
- Who repairs roof damage?
- Who is responsible for insurance?
The annual rent may look attractive.
24. Measure payback properly
Suppose a solar installation costs:
£120,000
and generates annual savings and income of:
£18,000
A simple payback calculation would be:
£120,000 ÷ £18,000 = 6.7 years
That looks attractive.
But it is incomplete.
A proper financial model should also consider:
- Finance costs.
- Maintenance.
- Insurance.
- Inverter replacement.
- Panel degradation.
- Export price changes.
- Electricity price changes.
- Tax treatment.
- Downtime.
- Grid charges.
- Monitoring fees.
- Opportunity cost of capital.
For larger projects, farmers should consider measures such as:
- Net present value.
- Internal rate of return.
- Discounted payback.
- Sensitivity analysis.
The contractual obligations can be more important.
25. Always run a bad-case scenario
Sales projections usually show expected performance.
Farmers should also calculate what happens if conditions are worse.
For example:

These figures are illustrative only.
If a project remains financially acceptable under conservative assumptions, the investment case is considerably stronger.
26. Generation guarantees need careful reading
A quotation may include a prediction such as:
“Expected annual generation: 150,000 kWh.”
That does not necessarily mean the installer guarantees 150,000 kWh.
Read the contract carefully.
Ask whether the figure is:
- A modelled estimate.
- A performance warranty.
- An equipment warranty.
- An insured guarantee.
These are very different things.
27. Renewable equipment must be insured correctly
Do not assume farm insurance automatically covers a major renewable installation.
Tell the insurer before installation.
Important issues can include:
- Fire.
- Lightning.
- Storm damage.
- Theft.
- Business interruption.
- Machinery breakdown.
- Public liability.
- Battery systems.
- Roof loading.
- Loss of renewable income.
Insurers may have specific requirements regarding equipment location and installation standards.
28. Cybersecurity is becoming part of farm energy security
Modern renewable installations are increasingly connected to the internet.
Solar inverters, batteries, energy management systems and smart meters may all have remote-access capability.
That brings convenience, but also creates cybersecurity issues.
Farmers should ask:
- Who has remote access?
- Is two-factor authentication available?
- Are default passwords changed?
- Who supplies software updates?
- Where is the operational data stored?
- What happens if the cloud service closes?
- Can the system operate without internet access?
Farm cybersecurity is becoming increasingly important as more machinery and infrastructure become connected.
29. Combining solar, wind and batteries can be more powerful than using one technology alone
A farm may discover that no single renewable source perfectly matches its demand.
Solar can perform strongly during summer days.
Wind may produce more during different weather and seasonal conditions.
Hydro may provide relatively continuous generation where the resource exists.
A battery can move some of that energy from one time period to another.
The farm can therefore be designed as an energy system rather than as a collection of unrelated machines.
Example
Solar → Battery → Dairy parlour → Milk cooling
During the day solar charges the battery.
During an evening milking, stored electricity helps supply the parlour and refrigeration load.
The actual economic benefit depends on generation, demand patterns, tariffs and system losses, but matching technologies can substantially improve utilisation.
30. Sometimes energy efficiency beats renewable generation
Before spending £100,000 generating additional electricity, ask whether £20,000 could reduce consumption permanently.
Possible improvements include:
- LED lighting.
- Variable-speed drives.
- Better insulation.
- Efficient refrigeration.
- Heat recovery.
- High-efficiency motors.
- Better ventilation controls.
- Improved grain-drying management.
- Fixing compressed-air leaks.
- Smart controls.
The cheapest unit of energy is often the one the farm no longer needs to buy.
Energy efficiency can also allow the renewable installation to be smaller and cheaper.
31. The farm should have an energy hierarchy
A sensible order is:
1. Measure consumption
↓
2. Eliminate unnecessary energy use
↓
3. Improve efficiency
↓
4. Generate renewable energy
↓
5. Increase self-consumption
↓
6. Store surplus where financially sensible
↓
7. Export remaining electricity
That approach prevents expensive generation equipment from compensating for avoidable waste.
32. Farming electricity demand may rise considerably
Renewable investment should consider what the farm may look like in 10 or 20 years.
Future electricity demand could increase through:
- Electric tractors.
- Electric loaders.
- Electric vans.
- Heat pumps.
- Robotic milking.
- Automated feeding.
- Grain drying.
- Irrigation.
- Refrigeration.
- Farm diversification.
- Workshops.
- EV charging.
Government energy policy anticipates significant long-term growth in electricity demand as more sectors electrify. GOV.UK
A system designed solely around today's electricity bill may therefore underestimate future opportunities.
33. But do not wildly oversize a system because “electricity will probably be needed”
Future demand should be based on a real business plan.
If the farm might purchase electric machinery in eight years, that does not automatically justify buying a huge solar array today.
Technology prices, tariffs and equipment may change.
A modular system that can be expanded could sometimes be more sensible.
34. Renewable energy grants can change — never assume an old scheme still exists
Agricultural renewable-energy support has changed repeatedly.
A grant advertised several years ago may no longer exist.
Eligibility can also depend on:
- Country within the UK.
- Farm type.
- Business structure.
- Technology.
- Installation date.
- Project size.
Always verify current funding conditions directly with the relevant government body before using a grant in the project's financial case.
The same applies to subsidy schemes.
For example, both the domestic and non-domestic Renewable Heat Incentive schemes are closed to new applicants.

36. Ask installers who actually carries the risk
Before choosing a contractor, establish:
- How long has the company traded?
- Who provides the equipment warranty?
- Who provides the workmanship warranty?
- What happens if the installer disappears?
- Who handles grid applications?
- Who handles planning?
- Who monitors performance?
- Who responds to faults?
- Where are replacement parts sourced?
- Is there a service agreement?
A 25-year panel warranty is not particularly useful if nobody is available to deal with a failure.
37. Keep renewable performance records
Once installed, monitor the system.
Record:
- Daily generation.
- Monthly generation.
- Imported electricity.
- Exported electricity.
- Self-consumed electricity.
- Battery charge/discharge.
- Faults.
- Maintenance.
- Downtime.
- Income.
- Savings.
A 200 kW system that quietly loses 15% of output through a fault could cost the farm substantial money before anyone notices.
Monitoring should therefore be considered part of maintenance.

The most powerful part is the expected versus actual column.
That quickly shows whether the project is performing as promised.
39. Questions to answer before spending £1
Before signing anything, answer these:
1. How much electricity and heat does the farm currently use?
2. At what time of day is it used?
3. How much could be eliminated through efficiency improvements?
4. Which renewable resource is strongest on this farm?
5. How much generation can realistically be consumed on site?
6. What export capacity is available?
7. Does planning permission apply?
8. What is the system's complete installed cost?
9. What maintenance is required?
10. What is the equipment lifespan?
11. What major component replacements are likely?
12. What happens when warranties expire?
13. What happens if electricity prices fall?
14. What happens if generation is lower than forecast?
15. What happens when the farm changes hands?
16. Who removes the equipment at the end of its life?
If these questions cannot be answered, the project is not ready.