Solar shading company reduces air conditioning usage by up to 68% at NHS hospital in Hampshire, solving Covid-19 ventilation problem. @Smartlouvre

Smartlouvre are the only manufacturers of the world’s thinnest and lightest sustainable louvred metal fabrics, MicroLouvre. The lightweight screens that easily attach to the outside of any windows have exceptional solar shading, natural ventilation and daylighting capabilities. Laboratory tests and previous case studies have proven that MicroLouvre can save up to 68% in air conditioning usage (Lawrence Berkeley National Laboratory, 2016, 3). This extraordinary finding makes MicroLouvre the solution not just for heat reduction, but also the serious issues with COVID-19 caused by inadequate and dangerous ventilation systems. MicroLouvre has provided huge benefits for both patients and staff at an NHS Hospital in Hampshire.

The fact that coronavirus is transmissible by airborne particles (The Lancet Respiratory Medicine, 2020:1159) means it has been recommended that hospitals, care homes, schools and public buildings find ways to naturally ventilate and reduce temperatures inside the building (Health and Safety Executive, 2021). In high rise buildings (such as hospitals) temperatures on wards can reach staggering heights of 30+ degrees centigrade (Siddique, 2021). Considering that germs breed in hot climates, this is a serious concern in the upcoming months.

In April 2020, at the beginning of the coronavirus pandemic, Smartlouvre was commissioned to install MicroLouvre screens on the Microbiology laboratory at an NHS Hospital in Hampshire on a trial run basis. The installer, Tim Powell, was met with initial resistance from the laboratory technicians as they were concerned that they wouldn’t be able to use their mobile air conditioning units which hang out of the windows. As chance would have it, whilst Tim Powell was explaining that the introduction of the MicroLouvres Screens would render their portable air conditioning units redundant, a Ward Sister walked past overhearing the exchange, and found that the product was exactly what they needed on her ward. She demanded that the Facilities Manager provide them for her ward, after receiving continuous complaints from staff and patients that the living and working conditions were unbearably hot especialliy when heavily covered in PPE. Despite questions over budget, by June 2020, MicroLouvre screens had been installed for the laboratory and the entire ward. The vast improvement was soon noticed, and the hospital no longer needed 40 new mobile air conditioning units, the laboratory technician air con machines were made redundant, and the windows could easily be opened for natural ventilation.

In 2015, Smartlouvre bought the rights to produce MicroLouvre, previously known as Koolshade, which has been being installed onto properties all around the world for more than 60 years. Due to the louvres being woven from corrosion-resistant, non- combustible, 90% recycled copper alloys, MicroLouvre are able to stand the test of time, proven with the many buildings that had the product fitted in the 1960s, still benefiting, with zero maintenance from the initial installation. Its eco-friendly properties make it a revolution in clean energy, with the product being 100% recyclable and drastically reducing the need for artificial cooling systems.

In 2020, Smartlouvre teamed up with simulation software company, Simscale. Using a simulation of the exact metrics of the product, they were able to calculate and prove the efficiency of MicroLouvre for today’s building modelling, previously only determined from practical use. Imputing a face-on open area of 67%, which increases to a phenomenal 80% at the 17° louvre angle, and a weight of only 1.1kg/m2, the pressure drop measured for 220mm x 220mm was only 40Pa, a discharge coefficient equivalent to a 400mm x 400mm square top hung window tilted outward 45deg nearly 3.5 times bigger! The simulation also showed that air passing through the angled louvres created an upward laminar airflow, inducing a current of air that moves across the ceiling and more effectively distributes clean air through the room (Simscale, 2020).

Based on the above simulations, Smartlouvre and Simscale were able to prove that the product passes the threshold for multiple accreditations under the world’s leading sustainability assessment method, BREEAM, including HEA4 Credit for thermal comfort and reducing overheating risk, and ENE1 Energy Credit for reducing cooling demand leading to lower electricity use and carbon emissions. It also surpasses the GLA overheating criteria to reduce high risk of solar gains and thermal comfort issues on glass buildings, LEEC EA Energy Credit to reduce demand, use free energy, and increase efficiency, as well as the Indoor Environmental Quality (EQ) for Ventilation Effectiveness, Thermal Comfort, and Daylight and Views.

Additionally, studies carried out by the California Lawrence Berkeley National Laboratory (LBNL) for a leading US Energy Company (Lawrence Berkeley National Laboratory, 2016, 65), concluded that the larger the surface area that MicroLouvre is covering, the more effective it is likely to be. Furthermore, using their data for CO2 emissions reduced by MicroLouvre, Smartlouvre calculated the approximate CO2 savings over the lifespan of a building with MicroLouvre. LBNL’s study used results based on two clear sunny days in October 2015, with both buildings with and without MicroLouvre having south facing windows, glazing and HVAC system, and a room temperature of 21 degrees centigrade. The results showed that you save 0.78kWh/m2 per day, which means, using The United States Energy InformationAgency’s publication from 2018 that 0.99lbs of CO2 is produced to deliver 1kW of electricity, assuming that an average building has a lifespan of 50 years, and you would usually need air conditioning for around five months of the year, you would save approximately 2.9 short tonnes (US) of CO2, or 2.6 metric tonnes of CO2/m2!

Smartlouvre has the opportunity to revolutionise the clean energy solar industry and solve the ventilation issue during the current COVID-19 pandemic. For more information or to book your free sample, head over to or call on +44 239 245 6333.



Lawrence Berkeley National Laboratory (2016) Technology Assessments of High Performance Envelope with Optimized Lighting, Solar Control, and Daylighting. Available at [Accessed 1 March 2021].

(2020) Covid-19 Transmission – up in the air. The Lancet Respiratory Medicine 8 (12) 1159. Available at:, [Accessed 17 February 2021].

Health and Safety Executive (2020) Ventilation and air conditioning during the coronavirus (COVID-19) pandemic. Available at: [Accessed 26 February 2021].

Siddique, H. (2018) NHS faces ‘summer crisis’ as heatwave sees record numbers at A and E. The Guardian. Available at: [Accessed 17 February 2021].

Simscale (2020) Smartlouvre Technology Ltd. Validates the Performance of a MicroLouvre™ Screen for Low Energy Building Design With SimScale’s Cloud-Based Platform. Available at: [Accessed 25 February 2021].