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The IEA supports international energy technology research, development, deployment, and knowledge transfer through multilateral groups (formally called Implementing Agreements). The experts participating in the activities of the Implementing Agreements represent public and private sector entities worldwide. Together, these experts share knowledge – and resources – to advance energy technologies.


Solar Heating and Cooling

As weather forecast models show varying results, combining satellite images with radiation and wind field data yields more accurate forecasts.*

Weather forecasts and satellite images

Policy context
Solar heating and cooling (SHC) technologies can be used for a wide range of applications, from residential domestic hot water and space heating and cooling to industrial and agricultural processes. Combined with energy storage, SHC technologies can provide continuous energy supply. Policies and measures to support deployment of SHC technologies include fiscal incentives such as feed-in tariffs, renewable portfolio standards for commercial heat and subsidies, or consumer tax incentives. Regulatory approaches such as solar obligations or building regulations are also effective. Training for trade and building professionals and consumer awareness campaigns should also be considered.

Background
The aims of the Implementing Agreement for a Programme to Develop and Test Solar Heating and Cooling Systems (SHC IA) are to overcome barriers and increase the solar global market share through research, development and testing of hardware, materials and design tools; expand the solar thermal market; and raise awareness of policy makers and consumers. There are currently 21 Contracting Parties, including China, Mexico, Singapore and South Africa, and one Sponsor.

Spotlight
Knowledge of solar energy resources is critical when designing, building and operating successful solar systems. High penetration of electricity from solar technologies will require more precise forecasting techniques to meet fluctuations in both weather and demand.

For these reasons the SHC IA project, Solar Resource Assessment and Forecasting, aims to improve validation procedures of existing solar resource data so as to gain a clearer understanding of the accuracy of various methods that forecast solar radiation from a few minutes to three days in advance. Preliminary results from the project show that for forecasts of less than one hour, critical for system operators seeking to match varying supply with varying demand, application of Total Sky Imagers or all sky cameras appears promising as they provide images of how the radiation will change over the next several minutes. Participants also investigated the reliability of forecasts derived from cloud motion vectors (CMV), based on a time series of cloud images from satellite observations.

Results show that the CMV model is most suitable for up to four-hour forecasts, while numerical weather prediction (NWP) models are more accurate for four- to six-hour forecasts.

However, synthesising results from a combination of both CMV and NWP models were found to be more accurate, whether over single sites or large regions. Another method consists of combining satellite images of cloud and radiation fields with wind fields from the weather research and forecasting (WRF) model. This was found to achieve optimum forecasting results compared to real weather conditions up to six hours in advance. The results provide best practices on solar energy resources to assist policymakers and project developers in advancing solar energy integration worldwide. 

* Source of the graph: Prediction of Solar Irradiance and Photovoltaic Power in Comprehensive Renewable Energy, Volume 1, pp239 - 292. DOI: 10.1002/pip.1224.

 


Current projects

  • Advanced lighting for retrofitting buildings
  • Compact thermal energy storage
  • Large-scale solar heating and cooling systems
  • Polymeric materials
  • Quality assurance and support measures for solar cooling systems
  • Solar and heat pump systems
  • Solar energy in urban planning
  • Solar heat integration in industrial processes
  • Solar rating & certification procedures
  • Solar renovation of non-residential buildings
  • Solar resource assessment and forecasting

For more information: www.iea-shc.org

Participants



Implementing Agreement information or material, including Implementing Agreement information or material published on this website, does not necessarily represent the views or policies of the IEA Secretariat or of the IEA’s individual Member countries. The IEA does not make any representation or warranty (express or implied) in respect of any IA Information (including as to its completeness, accuracy or non-infringement) and shall not be held liable for any use of, or reliance on, such IA Information.