Validation and Verification
After the implementation of the selected solutions for different retrofitting areas, validation and verification of their effect must be done to evaluate if the actuation corresponds to the expected performance and verify the achievement of the desired energy efficiency and comfort level.
The main issues to be assessed at this stage include the final energy performance, the carbon footprint impact and the indoor comfort parameters with respect to expected target as well as the safety of the components during installation, operation and maintenance. Also the durability and the performance of the solution for a certain period of time must be assessed, by collecting energy consumption, temperature and humidity data from sensors installed on different parts of the building components.
To perform a sound post-retrofit assessment, it would be beneficial to monitor the building for a period of 12 months before starting the retrofit process and for another 12 months after retrofit, in this way, reliable data in pre and pro-retrofitting conditions can be collected and enable a proper comparison and validation. A post-retrofit assessment of the building must be conducted following a standardized validation and verification methodology, aiming to make sure that the best practices are in place to maximize the retrofit investment value.
A useful tool for the performance evaluation and optimization is simulation model. The model that was built for the Energy Auditing and Performance Assessment (section 4) must be set up at the beginning considering the interactions between the building (demand side) and the specified HVAC system (supply side), then after the installation and commissioning of the system and the monitoring activities, the simulation model need to be calibrated and validated using the monitoring data. In this way, in the process of calibration and making the simulated results sufficiently correspond to real measured energy consumption, it will allow identifying the gaps and evaluating the building pathologies that could justify the gap between theoretical and experimental performance, and consequently, to locate the inefficiency or problems, afterward, further performance optimization of the building will be also carried out under the guide of the identified inefficiency.
Along with the energy performance assessment of the retrofitting project, end-user acceptance and public satisfaction evaluation need to be carried out. This task involves the evaluation of satisfaction among the commercial building owner, customers, employees and facility manager with the operation of the installed systems and technologies, and is tightly connected with the surveys done at the beginning of the project.
For this evaluation, besides the monitoring and assessment of some quantifiable indicators (thermal comfort and energy performance must be compared with the pre-retrofit building data), questionnaires will be done for the four types of aforementioned end user in order to collect their feedback based on their experiences.
Questionnaires will be distributed one year after the retrofitting project is concluded and will be collected to further assess the evaluation of system performance and project outcomes from a different angle, and to have perception from the user acceptance evaluation. The questionnaires will address various aspects including:
- Retrofitting actuation, in terms of the indoor comfort parameters of the building. This questionnaire will be mainly oriented to the clients and employees.
- Retrofitting project profitability in terms of direct and indirect economical parameters. This questionnaire will be done to the building owner. The questions and answers provided in the “Appendix 7. Owner questionnaire” at the beginning of the project will be retrieved to analyse the expectations and objectives of the owner and the current real state and market position of the building.
- User Interfaces of the Intelligent Automation Unit, which could include easiness in use, attractiveness, variety of data and visualizations of the results, usefulness for defining the optimal strategy, reliability, improvement of building energy performance management, energy savings, system´s failures etc.. This questionnaire will be mainly oriented to building facility manager.