[{"command":"openDialog","selector":"#drupal-modal","settings":null,"data":"\u003Cdiv id=\u0022republish_modal_form\u0022\u003E\u003Cform class=\u0022modal-form-example-modal-form ecl-form\u0022 data-drupal-selector=\u0022modal-form-example-modal-form\u0022 action=\u0022\/en\/article\/modal\/12303\u0022 method=\u0022post\u0022 id=\u0022modal-form-example-modal-form\u0022 accept-charset=\u0022UTF-8\u0022\u003E\u003Cp\u003EHorizon articles can be republished for free under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence.\u003C\/p\u003E\n \u003Cp\u003EYou must give appropriate credit. We ask you to do this by:\u003Cbr \/\u003E\n 1) Using the original journalist\u0027s byline\u003Cbr \/\u003E\n 2) Linking back to our original story\u003Cbr \/\u003E\n 3) Using the following text in the footer: This article was originally published in \u003Ca href=\u0027#\u0027\u003EHorizon, the EU Research and Innovation magazine\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003ESee our full republication guidelines \u003Ca href=\u0027\/horizon-magazine\/republish-our-stories\u0027\u003Ehere\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003EHTML for this article, including the attribution and page view counter, is below:\u003C\/p\u003E\u003Cdiv class=\u0022js-form-item form-item js-form-type-textarea form-item-body-content js-form-item-body-content ecl-form-group ecl-form-group--text-area form-no-label ecl-u-mv-m\u0022\u003E\n \n\u003Cdiv\u003E\n \u003Ctextarea data-drupal-selector=\u0022edit-body-content\u0022 aria-describedby=\u0022edit-body-content--description\u0022 id=\u0022edit-body-content\u0022 name=\u0022body_content\u0022 rows=\u00225\u0022 cols=\u002260\u0022 class=\u0022form-textarea ecl-text-area\u0022\u003E\u003Ch2\u003EGreener greenhouses promise more energy-efficient growing power\u003C\/h2\u003E\u003Cp\u003EIn the province of Almer\u00eda in southeastern Spain, farmers grow an estimated 2.5 to 3.5 million tonnes of fruit and vegetables every year in what has become known as Almeria\u2019s\u0026nbsp;\u003Ca href=\u0022https:\/\/earthobservatory.nasa.gov\/images\/150070\/almerias-sea-of-greenhouses\u0022\u003Esea of greenhouses\u003C\/a\u003E. In this region, greenhouses stretch as far as the eye can see, covering an area of over 40\u0026nbsp;000 hectares (400 square kilometres).\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EIt\u2019s partly thanks to this production that consumers across the continent can enjoy foods such as cucumbers, tomatoes and melons throughout the year. But there\u2019s a catch, these greenhouses aren\u2019t always very sustainable in terms or energy or water use.\u003C\/p\u003E\u003Cp\u003ESerena Danesi is a research associate at the\u0026nbsp;Institute of Energy Systems and Fluid Engineering (IEFE) in Zurich, Switzerland. She specialises in thermal engineering and heat recovery and, over the past four years, has been leading\u0026nbsp;the\u0026nbsp;\u003Ca href=\u0022https:\/\/cordis.europa.eu\/project\/id\/101000801\u0022\u003ETheGreefa\u003C\/a\u003E project that received funding from the EU to\u0026nbsp;develop a new, more energy-efficient and environment-friendly system for controlling both temperature and humidity in greenhouses.\u003C\/p\u003E\u003Cp\u003EIf Europe wants to meet its climate targets, and set the standard for sustainable food production \u2013 a goal set out in the EU\u2019s\u0026nbsp;\u003Ca href=\u0022https:\/\/food.ec.europa.eu\/horizontal-topics\/farm-fork-strategy_en\u0022\u003EFarm to Fork\u003C\/a\u003E strategy adopted in 2020 \u2013 then improving the sustainability of greenhouse farming will be a key concern.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u2018If we want to eat cucumbers, tomatoes and watermelons all year round, we need to be aware that their cultivation consumes a lot of energy and water,\u2019 said Danesi.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EClimate control\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EChanges in climate conditions and a need to have more control over the growing environment of crops have led to a rapid expansion of commercial greenhouse cultivation across Europe.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EIt was estimated, in 2018, that Europe had some\u0026nbsp;\u003Ca href=\u0022https:\/\/research.rabobank.com\/far\/en\/sectors\/regional-food-agri\/world_vegetable_map_2018.html\u0022\u003E210\u0026nbsp;000 hectares\u003C\/a\u003E (2\u0026nbsp;100 square kilometres) of greenhouses, with particularly high concentrations in Spain (70\u0026nbsp;000 ha), Italy (42\u0026nbsp;800 ha), France, the Netherlands, and in Central and Eastern Europe.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EThe energy needs of greenhouses differ, however, depending on their location. TheGreefa brings together researchers from\u0026nbsp;Italy, France, Germany, Spain, Switzerland, Poland and Tunisia to investigate how their proposed\u0026nbsp;system performs in different climate zones.\u003C\/p\u003E\u003Cp\u003E\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003EOur system reduced thermal energy requirements by 56%.\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003ESerena Danesi, TheGreefa\u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\u003Cp\u003E\u2018Greenhouses in Central Europe need heat because it is cold there. On the other hand, in Spain, they need cooling in the summer,\u2019 said Danesi. \u2018So there are different problems for different parts of Europe.\u2019\u003C\/p\u003E\u003Cp\u003EIn addition to temperature, humidity control is also an issue. As water evaporates from plants in a process known as \u201ctranspiration\u201d, humidity levels rise and can become dangerously high. High humidity can cause fungal diseases, which can easily spread and destroy a crop. Moreover, if the humidity is too high, the plant will not be able to transpire normally and will die.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EHeat from humidity\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EThe ingenious solution proposed by the TheGreefa researchers allows greenhouse owners to use the moisture released naturally by the plants to generate heat. It also makes it possible to recuperate pure water from the excess humidity, thus saving on both water and energy.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EA salt solution absorbs any increased moisture in the greenhouse, releasing heat in the process through a thermo-chemical reaction.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u2018We can dehumidify the air and create heat all at the same time,\u2019 said Danesi.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EAn added benefit is that this absorption process eliminates the need for ventilation, drastically reducing the amount of heat lost when windows need to be opened to get rid of excess moisture.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EOnce the salt solution has absorbed as much water as it can, it can then be regenerated using low level heat produced by surplus solar power. This separates the salt and the water, leaving the salt solution ready to be stored and reused when needed.\u003C\/p\u003E\u003Cp\u003EThe dehydrating effect created by the salt solution can also be used for drying fresh produce like herbs and fruits to extend their shelf life. Because it works at low temperatures, qualities like smell and taste remain intact.\u003C\/p\u003E\u003Cp\u003EThe technology was tested in greenhouses in Switzerland and Tunisia. In Switzerland the focus was on heating and seasonal storage, while in the southern countries the focus was on energy efficiency and water recovery.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u2018We are now evaluating the results and we have seen some energy savings,\u2019 said Danesi. \u2018In the Swiss greenhouse, our system reduced thermal energy requirements by 50%.\u2019\u003C\/p\u003E\u003Cp\u003EAlthough promising, widespread application of this technology in commercial greenhouses is still some way off. Pilot testing will, for the time being, continue in smaller-scale environments before moving on to a larger scale.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EFarming goes solar\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EAnother way in which greenhouses could become more sustainable would be to take advantage of the fact that these structures occupy large areas bathed in sunlight. That puts greenhouses in a unique position to use sunlight to generate clean electricity.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EOne challenge, however, is that solar panels tend to be opaque, so they can\u2019t be placed over crops, otherwise these won\u2019t grow. This was the challenge that electrical engineer Nick Kanopoulos decided to take on in a three-year EU-funded project called\u0026nbsp;\u003Ca href=\u0022https:\/\/cordis.europa.eu\/project\/id\/804554\u0022\u003EPanePowerSW\u003C\/a\u003E that ended in 2021.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003EWe think the wide use of this technology will decarbonise agriculture to a great extent.\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003ENick Kanopoulos, PanePowerSW \u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\u003Cp\u003EKanopoulos is CEO of the start-up company Brite Solar based in Thessaloniki, Greece, that specialises in next-generation solar technology.\u003C\/p\u003E\u003Cp\u003E\u2018We wanted to build a solar panel suitable for agriculture so that, on the same land, we can produce both crops and energy without one impeding the other,\u2019 he said.\u003C\/p\u003E\u003Cp\u003EKanopoulos and his team developed a solar panel coated with nanomaterials that absorb light particles in the UV range of sunlight, which are not useful for either photovoltaic panels or growing plants. It then re-transmits them in the red and blue ranges of the visible spectrum, which are useful for both.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EVisible light is thus able to pass through the panels while boosting both electricity production and photosynthesis, making the technology ideal for use in greenhouses.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EClean energy benefits\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EThe team tested the panels in greenhouses in Greece, Spain, the US and Singapore, and in open field cultivation in Germany, France, the Netherlands and Romania. Tests were run on different crops, including tomatoes, blueberries, ornamental flowers and pear trees. Their results showed that farmers can significantly reduce their carbon dioxide footprint by generating clean energy while growing crops.\u003C\/p\u003E\u003Cp\u003EBesides farmers being able to produce their own energy, the innovative greenhouse structure offers further advantages. It collects rainwater for use on the crops and provides protection against adverse weather. It also reduces water evaporation, resulting in a significant drop \u2013 about 20-40% \u2013 in the water needed for irrigation.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EKanopoulos\u2019 team is now expanding and building a factory in Greece to automate and speed up the production of solar glass. He said that with this factory, the company will be able to combine nano-coating application with solar panel assembly, all in one production line.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EThis will help them reach more customers, both small and large farmers, in an effort to make the agricultural sector more sustainable.\u003C\/p\u003E\u003Cp\u003E\u2018We think the wide use of this technology will decarbonise agriculture to a great extent and contribute to sustainable food production,\u2019 said Kanopoulos.\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EResearch in this article was funded by the EU\u2019s Horizon Programme. The views of the interviewees don\u2019t necessarily reflect those of the European Commission. If you liked this article, please consider sharing it on social media.\u003C\/em\u003E\u003C\/p\u003E\u003C\/textarea\u003E\n\u003C\/div\u003E\n\n \u003Cdiv id=\u0022edit-body-content--description\u0022 class=\u0022ecl-help-block description\u0022\u003E\n Please copy the above code and embed it onto your website to republish.\n \u003C\/div\u003E\n \u003C\/div\u003E\n\u003Cinput autocomplete=\u0022off\u0022 data-drupal-selector=\u0022form-yxnv3ugnsrf6tgguqcew7bmnq4znrluj53lwjjqapm\u0022 type=\u0022hidden\u0022 name=\u0022form_build_id\u0022 value=\u0022form-_yXnv3ugNsrF6tGGUQcew7bMnQ4ZNRluj53lWJJQaPM\u0022 \/\u003E\n\u003Cinput data-drupal-selector=\u0022edit-modal-form-example-modal-form\u0022 type=\u0022hidden\u0022 name=\u0022form_id\u0022 value=\u0022modal_form_example_modal_form\u0022 \/\u003E\n\u003C\/form\u003E\n\u003C\/div\u003E","dialogOptions":{"width":"800","modal":true,"title":"Republish this content"}}]