Defra - Department for Environment, Food and Rural Affairs.

Science Search

Science and Research Projects

Return to Science Search homepage   Return to Project List

Energy saving through an improved understanding and control of humidity (WG) - HH3611SPC

The United Nations, Kyoto protocol, to which the UK is a signatory, calls for a reduction in ‘greenhouse gas’ emissions during the period 2008 to 2012 to a level, at least 5% below 1990 levels. From the UK agricultural standpoint this requires the development and implementation of practices that are both energy efficient and sustainable. Horticulture is by far the most energy-intensive sector of agriculture, consuming 20.2 PJ energy per annum and, in return for receiving a 50% reduction in the Climate Change Levy, has committed itself to making a 15% reduction in its energy use by the year 2010. However, to achieve this and to remain viable, new approaches are needed, and the work proposed here is intended to contribute to this. This project, therefore, addresses the Defra policy objective to develop horticultural production systems that use natural resources efficiently and consistently with the principles of sustainable development (HH36: Sustainable use of natural resources and labour). A collaborative project bringing together physiology, pathology and environmental physics expertise is proposed. This work will build upon current research at HRI (with support from SRI) on the effects of temperature on plant growth and quality, sensing of canopy-based humidities and fungal pathology. The experiments will focus on tomato (as a model high-wire crop with a substantial canopy) and chrysanthemum, petunia and pansy (as model pot and bedding plants). The pathology work will focus on botrytis, although white rust will be included to ensure that generic conclusions are obtained.
Overall aim – Provide a framework for temperature and humidity management, so as to enable maximal energy savings, while maintaining plant quality and minimal incidence of disease. The specific objectives are: 1. Develop an energy balance model for tomatoes, and use one already developed for ornamentals, to simulate the effect of different temperature regimes on energy consumption, so as to identify optimal energy saving strategies (years 1-4).2. Quantify the effect of different day/night temperature regimes on the yield and quality of tomatoes, using a controlled environment facility (year 1) and glasshouse compartments (year 2). 3. Assess the effect of using low pre-night temperatures on yield and quality of tomato grown under glasshouse conditions, and determine the implications for energy use using an energy balance model (year 3).4. Quantify the effect of different low day/high night temperature regimes on the quality of pot chrysanthemums grown during autumn/winter, and bedding plants (petunia and pansy) grown in spring (year 1).5. Determine for how long low day/high night temperature regimes can be used without adversely affecting quality in pot chrysanthemums and bedding plants when the remaining time is spent in a ‘standard’ regime (years 2) or a high day/low night regime (year 3).6. Define the effects of humidity on the germination of Botrytis spores and white rust (years 1-3). 7. Assess the impact of airborne inoculum concentrations on disease risk through the use of spore trapping on commercial nurseries (years 3 and 4).8. Recommend procedures for either monitoring or predicting canopy humidities, and develop and validate a strategy of humidity control to minimise disease risk while maximising energy savings in both tomatoes and ornamentals (years 3 and 4).9. To publicise the work through appropriate publications and presentations, and to liaise closely with key industry leaders to ensure take up of the work (years 1 to 4).
Project Documents
• Final Report : Energy saving through an improved understanding and control of humidity and temperature   (2096k)
Time-Scale and Cost
From: 2004

To: 2008

Cost: £1,072,198
Contractor / Funded Organisations
Warwick - HRI
Allocated - WHRI              
Biotech-non GM              
Climate Change              
Energy Efficiency              
Natural Resource Use              
Protected Cropping              
Sustainable Farming and Food