Solar sheds

Power Up Your Outbuilding: A Guide to Solar Sheds

Transforming your garden shed into a solar-powered hub offers a fantastic way to gain energy independence, reduce your carbon footprint, and even save on electricity bills. Whether you’re envisioning an off-grid man cave, a powered workshop, or a supplementary power source for your home, understanding the key considerations is crucial for a successful solar shed installation.
We have had a number of questions about off grid power supported by grid power in sheds, for a number of reasons, so this should cover a lot of things that you need to know…

Sizing Up Your Solar Shed: Roof and Panel Considerations

The first step in planning your solar shed is to assess your available roof space and determine the appropriate solar panel size and what power you are going to achieve.

• Panel Sizing: As a general guide, a shed roof aiming for 1500W of solar power per side will typically accommodate three standard solar panels. Each modern solar panel can range from 300W to 550W, do not forget that you need to use NMOCT ( standard normal use) figures.
• Roof Area: Factor in the dimensions of your shed roof. You’ll need sufficient clear space for the panels, avoiding obstructions like chimneys, vents, or overhanging trees that could cast shadows.
• Power Yield: With 1500W per side, a two-sided solar shed could potentially yield around 7200 Wh (Watt-hours) per day, depending on sunlight hours and panel efficiency. This is a significant amount of power for a shed, opening up a wide range of possibilities.

Structural Integrity: Weight, Snow Loads, and Upgrades

Solar panels add substantial weight to your shed’s roof and structure. Neglecting this crucial aspect can lead to costly and dangerous structural failures.

• Panel Weight: Three solar panels, depending on their size and construction, can weigh around 180kg when fitted. If you have panels on both sides of a gabled roof, you’re looking at a significant additional load.
• Snow Loads: In regions prone to snowfall, this weight is compounded by snow accumulation. Wet, heavy snow can add considerable stress to your roof.
• Roof and Wall Upgrades: It is highly advisable to assess and likely upgrade your shed’s roof and supporting walls. This may involve:
  • Reinforcing Roof Rafters: Adding more substantial or additional rafters to distribute the load.
  • Strengthening Wall Studs: Ensuring the walls can adequately support the roof’s increased weight.
  • Adding Lateral Bracing: To prevent racking or movement under load.
  • Foundation Review: For heavier systems, ensure your shed’s foundation is robust enough to handle the increased overall weight.
  • Professional Assessment: For larger systems or older sheds, consider consulting a structural engineer to ensure your building can safely support the solar array.
  • Most low cost DIY sheds will not support the loads.

Wiring for Power: Cables, Inverters, and Fire Protection

Proper electrical installation is paramount for safety and efficiency.

• Cable Sizing: All power cables, from the panels to the charge controller, inverter, and battery bank (if applicable), must be appropriately sized to handle the current without overheating. Undersized cables are a significant fire risk and lead to energy loss.
• Conduit and Protection: All outdoor and exposed wiring should be run in UV-resistant conduit to protect it from the elements, physical damage, and pests.
• Inverter and Charge Controller Placement: These critical components should be housed in a well-ventilated, dry, and secure location within the shed, away from flammable materials.
• Fire Protection:
  • DC Disconnects: Install easily accessible DC disconnect switches near the solar panels and the inverter. These allow you to quickly de-energize the system in an emergency or for maintenance.
  • AC Disconnects: For grid-tied or hybrid systems, an AC disconnect switch is also required to isolate the system from the grid.
  • Overcurrent Protection: Use correctly rated fuses or circuit breakers on all circuits to protect against overloads and short circuits.
  • Grounding: Properly ground all metallic components of the solar array and electrical system to prevent electrical shock in the event of a fault.
  • Arc Fault Circuit Interrupters (AFCIs): Consider installing AFCIs, especially for DC circuits, as they can detect dangerous electrical arcs that might not trip standard circuit breakers.
  • Regular Inspections: Periodically inspect your wiring for signs of wear, damage, or loose connections.

Off-Grid, Grid-Tied, or Hybrid: Choosing Your System

The purpose of your solar shed, often as a “man cave” running servers, CCTV, and entertainment, typically leans towards off-grid support. However, considering your power needs and future goals, there are different system architectures:

• Off-Grid System: This is ideal for complete energy independence. Power is generated by the panels, stored in batteries, and then used to power your shed’s appliances. A grid charge for winter is a sensible approach to ensure continuous power during periods of low sunlight.
  
• Grid-Tied System: If your primary goal is to offset household electricity costs and your shed has a large enough roof for significant generation, a grid-tied system is an excellent option. Excess power generated by the shed can be fed back into the main house or the grid, further reducing your energy bills. This is generally more complex and requires grid connection approvals.
  
• Hybrid System: Offering the best of both worlds, a hybrid system combines battery storage with a grid connection. This allows you to use stored solar power, supplement with grid power when needed, and even feed excess back to the grid. This option provides greater flexibility and resilience.
  
• Micro switchable: Using a micro inverter and the same solar panels for off grid, then when not in use, this powers the home, this can be a cost effective option.

Budget and Usage: Strategic System Design

Your budget and how you intend to use the shed are paramount in system design.

• Budget Considerations: Grid-parallel or hybrid systems are inherently more expensive due to the additional components and stealth taxes as well as paperwork
• Weekend Use vs. Daily Operation:
  • Weekend User: If your shed is primarily a weekend retreat, a smaller, purely off-grid system might be sufficient. However, a small grid-tied system offers flexibility. You could design a system with a manual or automated switch to transfer the solar power from the off-grid shed use to a grid-tied setup when the shed is not in use. This allows you to maximize your solar investment by contributing to your home’s power consumption.
    
  • Daily Operation/High Demand: For continuous use, especially with servers and CCTV, a more robust off-grid system with ample battery storage or a hybrid system with grid support will be necessary.
    
• Automation vs. Manual Control:
  • Manual System: A simpler, more budget-friendly approach where you manually switch between off-grid and grid-tied modes based on your usage. This gives you direct control.
  • Automated System: More sophisticated and convenient, an automated system can intelligently manage power flow between your panels, batteries, shed loads, and the grid. This maximizes efficiency and ensures continuous power without manual intervention. While more expensive upfront, it offers significant long-term convenience and optimization.

By carefully considering these factors, you can design and build a solar shed that perfectly meets your needs, providing reliable, sustainable power for years to come. When we ran the figures, you are looking at around £1500-£1800 for a system of this type, you could go over £2000 depending on what you want and which hardware you pick. You do not want to get caught up in hypes or paying too much and we offer a range of kits as well as support and advice.