Key Takeaways -

• Gas heaters offer high heat output and cost-efficiency, ideal for larger greenhouses.
• Electric heaters provide clean, emission-free heating and are easier to use in smaller spaces.
• Gas heaters have lower running costs but require proper ventilation and regular maintenance.
• Electric heaters are more eco-friendly when powered by renewable energy but have higher running costs.

Heating your greenhouse is essential for keeping plants healthy during colder months. Choosing between gas and electric heaters depends on factors like size, cost, environmental impact, and ease of use.

This article will explore the differences between gas and electric heaters, highlighting important factors such as costs, safety, and eco-friendliness.

Keep reading to find out which type of heater best suits your greenhouse needs. No matter your choice, understanding each option's pros and cons will help you create a warm and productive growing environment.

Types of Gas Greenhouse Heaters

Propane Gas Greenhouse Heaters

Propane gas heaters are a popular choice for greenhouses due to their high heating efficiency, making them ideal for larger spaces. They are portable and can be used in remote locations without a mains connection. These heaters produce high heat output, which can be cost-effective in certain situations.

However, propane heaters require frequent cylinder replacements, which can be inconvenient, and they emit carbon dioxide and water vapour, which can impact plant health and contribute to greenhouse gas emissions. Regular maintenance is crucial to ensure safe and efficient operation.

Natural Gas Greenhouse Heaters

Natural gas heaters are a cost-effective option for long-term use, as they typically have lower running costs than electricity. These heaters provide a continuous gas supply when connected to the mains, making them convenient for consistent heating.

However, installation costs can be high, particularly for smaller greenhouses, and they are not as environmentally friendly due to greenhouse gas emissions.

Despite the drawbacks, natural gas heaters are a reliable choice for those looking for consistent heat in larger greenhouse setups with access to mains gas.

Types of Electric Greenhouse Heaters

Electric Fan Heaters

Electric fan heaters are a popular choice for greenhouse heating as they provide clean energy and consistent heat distribution. These heaters improve air circulation, reducing cold spots and preventing issues like mould.

They often offer dual functionality, acting as fans during warmer months to keep air moving. Electric fan heaters are easy to use and produce no harmful emissions, making them suitable for sensitive plants.

However, they can be expensive to run due to higher electricity costs and require a stable electric supply, which can involve additional setup expenses.

Tube Heaters

Tube heaters are an efficient choice for providing cost-effective background heat and preventing frost in greenhouses. These heaters are particularly suitable for smaller greenhouses, as they produce lower heat output but are reliable for maintaining a stable temperature.

They are easy to install and operate, offering a simple solution for keeping plants warm during colder months. However, tube heaters may not be effective in very cold conditions or for larger spaces where higher heat output is needed for optimal plant growth.

Gas vs Electric Greenhouse Heaters: Cost Comparison in the UK

Initial Costs

Electric heaters generally have lower upfront costs, with basic models starting at less than £20 and more advanced options costing around £400. In contrast, gas heaters, including propane and natural gas models, often have higher initial equipment costs due to their heating efficiency.

Installation costs vary significantly: installing a gas central heating system can cost around £5,250, while an electric heating system costs approximately £3,790.

Connecting a gas heater to the mains can be expensive and impractical for smaller greenhouses, whereas electric heaters usually only require an outlet for operation.

Running Costs

In the UK, gas is generally cheaper than electricity per kilowatt-hour (kWh), with gas costing around 6.04p/kWh compared to electricity at 24.5p/kWh. The lower unit cost of gas results in significantly lower running costs over time.

For example, the average annual cost for gas heating is about £708, while electric heating can reach approximately £3,370 per year. Although propane heaters may cost about 19p per hour to operate, natural gas heaters remain the most economical option at roughly 7p per hour (1).

Maintenance Costs

Propane heaters require regular gas cylinder replacements, which adds to operational costs and can be inconvenient. Additionally, gas heaters need regular servicing to ensure safety and efficiency, which incurs further expenses.

In comparison, electric heaters typically require less maintenance, with no need for fuel replacements or risk of carbon monoxide emissions. Many electric heaters also offer dual functionality as fans during warmer months, enhancing their overall value and reducing the need for additional equipment.

Environmental Impact

Gas Heaters

Gas heaters produce carbon dioxide, water vapour, and, in some cases, carbon monoxide. While carbon dioxide can support plant growth, poor ventilation can lead to harmful gas buildup. Excess water vapour can also cause humidity-related issues like mould.

Proper ventilation is essential for safe use, ensuring good air quality for plants and users. Although gas heaters offer efficient heating, their emissions make them a less eco-friendly option compared to electric heaters.

Electric Heaters

Electric heaters produce no direct emissions, making them an environmentally friendly choice, especially when powered by renewable energy. Eco-tariffs in the UK allow users to source clean energy, reducing their carbon footprint.

Exhaust-free operation minimises harmful gases and makes electric heaters suitable for sensitive growing environments. Though more expensive to run, their emission-free heating supports sustainable gardening practices.

Sustainability Considerations

Electric heaters are generally more sustainable due to their zero-emission operation and compatibility with renewable energy. Gas heaters, while cost-effective for larger greenhouses, produce greenhouse gas emissions.

For those prioritising eco-friendly practices, electric heaters are the better option despite higher running costs, particularly when combined with green energy tariffs.

Choosing the Right Heater for Your Greenhouse

Small Greenhouses

For small greenhouses, electric heaters are often the best option due to their ease of use and environmentally friendly operation. Electric fan heaters provide consistent heat distribution, while tube heaters offer cost-effective frost prevention.

The lower upfront cost and minimal maintenance make electric heaters ideal for smaller spaces. Additionally, the clean, exhaust-free heat is beneficial for sensitive plants, and if powered by renewable energy, it further supports sustainable gardening practices.

Large Greenhouses

For larger greenhouses, gas heaters are typically more suitable due to their higher heat output and lower running costs. Propane heaters offer portability, while natural gas heaters provide a continuous fuel supply when connected to the mains.

Although initial costs can be higher, gas heaters are often more cost-effective for heating larger spaces over the long term. Proper ventilation is essential to safely manage emissions and maintain good air quality for plants.

Budget Considerations

When choosing a heater, it's important to balance initial investment against long-term running costs. Gas heaters often have higher upfront costs due to installation, but their lower fuel costs make them more affordable for continuous use.

In contrast, electric heaters have lower initial costs but higher electricity expenses. Weighing fuel costs versus electricity prices and considering factors like greenhouse size and heating duration will help determine the most cost-effective option for your needs.

Frequently Asked Questions

Do Gas Heaters Pose a Risk of Fire or Explosion in a Greenhouse?

Yes, gas heaters can pose a risk of fire or explosion if they are not properly installed or maintained. Gas leaks, faulty equipment, or improper handling of propane cylinders can increase the risk. However, modern gas heaters are equipped with safety features like flame failure devices to minimise danger.

Following safety guidelines and conducting regular inspections are essential for safe operation.

Can I Use Both Gas and Electric Heaters Together in My Greenhouse?

Yes, using both gas and electric heaters together can be a practical solution. A gas heater can serve as the primary heat source, while an electric heater can provide additional heat or improve air circulation during colder periods.

This approach helps maintain consistent temperatures and provides a backup option in case one heater fails. It can be particularly effective for large or temperature-sensitive greenhouses.

What Is the Lifespan of Gas vs. Electric Heaters in a Greenhouse?

The lifespan of a gas heater tends to be longer than that of an electric heater if maintained properly. Gas heaters are often built with durable materials and require regular servicing to ensure safe operation.

Electric heaters may have a shorter lifespan due to wear on electrical components, but proper care can extend their durability. Regular maintenance is key to maximising the longevity of both types.

Conclusion

In conclusion, choosing between gas and electric heaters for your greenhouse depends on your specific needs, including greenhouse size, budget, and environmental priorities. Gas heaters offer high heat output and lower running costs, making them ideal for larger setups.

Electric heaters provide clean, emission-free heating and are easier to use, especially in smaller spaces. By weighing the pros and cons of each option, you can select the best heating solution to create a warm and thriving environment for your plants.

Sources -

1. https://www.checkatrade.com/blog/cost-guides/gas-vs-electric-heat-cost-which-is-cheaper/