Green Roof Actual Evapotranspiration

When the subject of energy and green roofs comes up nearly everyone familiar with the topic will tell me that green roofs stay cool because of evapotranspiration.

Green roof actual evapotranspiration. Therefore artificial irrigation methods are required especially for green roofs in tropical countries. The plants in a green roof absorb water through their roots and then use surrounding heat from the air to evaporate the water while some roofs can reach temperatures of up to 90 f in the summertime these two features can allow. Evapotranspiration drives water requirements and hence irrigation scheduling and is the driver of retention. Needless to say this is a task best left to the experts.

Retention is water captured by the green roof that only leaves as vapor through the process of evapotranspiration. The dynamic behavior of green roof and building energy. An evapotranspiration module a flow routing module which utilized stormwater management model swmm and an infiltration module. Green roofs reduce the temperature of the building and the surrounding air in multiple ways.

Anna zakrisson on sunday may 26 2019. Evapotranspiration the rate in mm day at which water is transferred from the surface to the atmosphere by evaporation and transpiration on the green roof. Most of the analysed studies performed a comparison between green roof evapotranspiration plants substrate and bare soil evaporation only substrate. Retention and evapotranspiration are always the same volumes.

Evapotranspiration rates determine green roof retention by dr. The actual solar radiation reaching the earth surface depends by the turbidity of the atmosphere and the presence of clouds which reflect and absorb a large percentage of the radiation. The depth of depression storage or the amount of water that can be retained by the green roof in millimetres. The system is capable of predicting the evapotranspiration and deciding the amount of water to be irrigated based on that.

Particularly green roof performance is sensitive to local climate. Evapotranspiration why even when discussing it with professional engineers doing building energy modeling they assume that most of the cooling ability of a green roof is through. The main objective of this study was to evaluate the evapotranspiration effect of an extensive green roof on annual energy consumption of an office building in relation to the humid continental climate of republic of korea. Green roofs gr as decentralized green spaces can be installed to decrease the amount of rainstorm runoff on building rooftops by storing precipitation and facilitating actual evapotranspiration aet berardi et al 2014 hathaway et al 2008 reducing rooftop runoff mitigates the increased risk of flood damage in urban areas due to climate change asnaashari et al.

In late 2010 swmm released its own lid module in which green roofs can be modeled using the bioretention cell control. Evapotranspiration is the process of water escaping as vapor. She pang 2010 developed a physically based green roof model using three submodules.