How to reduce the environmental impact of greenhouses
How to reduce the environmental impact of greenhouses
Controlled environment agriculture is a method of farming that allows us to create optimum conditions for healthy and efficient plant growth - a greenhouse being perhaps the most traditional and common example. Globally, huge amounts of our food is grown in commercial greenhouses - with this method having become increasingly popular due to changing climates and unpredictable weather patterns.
So how can we make sure the environmental impact of greenhouses is limited? In this blog, we explore some of the different elements to consider and look at how aeroponics can help to maximise productivity, whilst reducing impact.
Construction
It’s important to take into account the initial environmental impact of building a greenhouse, especially when calculating its ongoing scope emissions. In the construction of a standard greenhouse, aluminum or steel is often used. Aluminum is infinitely recyclable - but the process is energy intensive and CO2 emissions from aluminum can be high, depending on where it’s sourced. Steel is considered to be more durable and more able to withstand extreme weather. These would be the most sustainable choices, but both with benefits and drawbacks to be considered.
Resource management
Operationally, there are many different resource elements to consider when running a greenhouse: from water, to pesticide and fertiliser use. With various irrigation system options, it’s possible to make significant improvements in water efficiency.
One of the most common irrigation systems in a greenhouse is hydroponics. By using LettUs Grow’s ultrasonic aeroponics, it’s possible to reduce water, fertiliser and pesticide use. In greenhouse trials, we’ve seen yield improvements of up to 20%, whilst using far less resources. Without the use of high-pressure nozzles which can easily become clogged and lead to downtime, greenhouse operations can run smoothly and efficiently with retrofittable Aeroponic Rolling Bench technology.
Thinking beyond CO2 emissions, it’s also key to consider other measures of sustainability, such as biodiversity. Limiting land use for agriculture is a huge part of protecting natural spaces, and boosting yields within greenhouses will help to achieve this.
Energy efficiency
Improving energy efficiency in a greenhouse is crucial to reducing emissions. Greenhouses already harness natural energy sources by using sunlight, but heating, environmental control, and sometimes additional lighting all need to be powered. Where energy is sourced from is one consideration where sustainability will have to be weighed up against cost and convenience. Many greenhouses use combined heat and power (CHP) gas boilers, which generate large amounts of CO2 and heat.
Generating energy on site, from solar panels for example, is preferable, however this incurs an upfront cost. It may also make sense to use two or more sources, so that farm operations can continue if one source is interrupted. If using energy from the grid, a provider that is using renewable energy is key to making sure environmental impact is limited.
If you want to learn more, download our Guide to Energy in Controlled Environment Agriculture.
Waste
Reducing waste in any capacity reduces environmental impact. Water and fertiliser should be recaptured and reused to limit waste, but also to prevent fertiliser runoff into natural ecosystems. Other elements to consider are materials such as matting and plugs - such as biodegradable or recycled options. Avoiding products with peat also has a huge impact on emissions - it’s set to be banned in the UK from 2026.
As well as reducing waste, there is also the possibility of using waste from other industries, such as heat sources. For example, locating a greenhouse next to an Anaerobic Digester plant will allow the grower to harness the heat that is generated as a byproduct of generating electricity. However this must also be monitored to make sure that this doesn’t create demand for emissions.
Data
In order to reduce the environmental impact of your greenhouse, you need to have a good idea of what impact it’s currently having. The best way to achieve this is to make sure that the growers operating a greenhouse facility can manage and analyse their own data. It’s important that those working on calculating scope 3 emissions are collaborating with growers and sharing that knowledge, so that those in control of operations can begin to make changes in their day to day tasks or in the greenhouse systems. Software and apps, such as our farm control software Ostara®, can go a long way in helping to collate data management and collection in one place.
Another aspect to consider is the energy and financial cost of crop recipes, which farm management software can record and forecast for you.
Innovation in the sector
The agricultural sector is fast-moving, but often policy is slow to change. Providing support to greenhouse managers so that appropriate life-cycle analysis can be conducted is key to gathering the data needed to implement change.
If you would like to learn more about how ultrasonic aeroponics & farm control software can help to reduce the environmental impact of your greenhouse, then get in touch.