The building sector is responsible for approximately 40 % of the total energy usage in Sweden. In office buildings the heating, ventilation and air conditioning system can account for up to 55 % of the energy usage. In order to reduce the energy usage of the heating, ventilation and air conditioning system different control methods are often used. One of these control methods is demand controlled ventilation, where the ventilation system is controlled with regard to occupancy with the help of motion and/or CO2 sensors. The aim of this thesis was to determine the energy savings potential of a heat recovery unit as well as demand controlled ventilation in an office building. The effect of longer intervals between sensor control signals to the ventilation system was also investigated. This is done by creating schedules, gathered from actual building occupancy, that are being used to control the occupancy and ventilation in a building model in the building performance simulation software IDA ICE. As a reference building, the fifth floor of the LU1 section of the natural science building at Umeå University is used. The reference building consists of 40 offices for which the occupancies are known. The average occupancy for all the offices combined throughout the investigated time period is determined to be 34.8 %. The results from the simulations indicate that an energy savings potential of 52.98 % can be achieved by a heat recovery unit with an efficiency of 80 % or 95 %, when compared to not having a heat recovery unit. When implementing demand controlled ventilation an energy savings potential of 2.8-11.0 % can be achieved, with the energy savings potential decreasing when the efficiency of the heat recovery unit increases. Finally, it is shown that longer intervals between sensor control signals to the ventilation system leads to a small increase in energy usage and poorer indoor air quality.

<p><p>This report describes the work of developing a specification of requirements for Waste Heat Recovery Units. The main part of the paper describes how the work with the specification of requirements has been performed. One specific question to be answered is:</p><p>What are the customer’s demands in case of properties for the Waste Heat Recovery Units and how is that information collected as an order documentation to suit the business area Oil & Gas?</p><p>The report begins with a description of the assignment and continues with the aim and background. A theoretical part describes the different areas and methods that have been important during the process. Work on the specification has been carried out on site at the company where interviews of staff and the study of internal documents has been a significant part of the implementation.</p><p>The result is delivered to the company in the form of a specification of requirements for the Waste Heat Recovery Unit. This specification fulfills the requirements set initially and is a good starting point for the company to proceed with in contact with subcontractors. The conclusion of the work is that the establishment of a good specification of requirements is really important and that has been obvious during the work and progress of this project. The difficulty lied in getting the right information and to keep it simple and at same time durable.</p></p>

This report describes the work of developing a specification of requirements for Waste Heat Recovery Units. The main part of the paper describes how the work with the specification of requirements has been performed. One specific question to be answered is: What are the customer’s demands in case of properties for the Waste Heat Recovery Units and how is that information collected as an order documentation to suit the business area Oil &amp; Gas? The report begins with a description of the assignment and continues with the aim and background. A theoretical part describes the different areas and methods that have been important during the process. Work on the specification has been carried out on site at the company where interviews of staff and the study of internal documents has been a significant part of the implementation. The result is delivered to the company in the form of a specification of requirements for the Waste Heat Recovery Unit. This specification fulfills the requirements set initially and is a good starting point for the company to proceed with in contact with subcontractors. The conclusion of the work is that the establishment of a good specification of requirements is really important and that has been obvious during the work and progress of this project. The difficulty lied in getting the right information and to keep it simple and at same time durable.