Final ReportSummary - ROOF-CAPTURE (Innovative Design for Wind Energy Capture in Urban Environments)
The overall industrial objective of the product is to develop a roof-mounted building augmented wind turbine module which will allow a small turbine to double its power output and which will also provide air heating and powered passive ventilation in the building below, cutting system payback time to an average of five years. The project has created knowledge relating to the air flow across flat roofed buildings and a model for how it can be best accelerated and channelled to achieve increases in ducted air over the free air stream so increasing the power yield from the turbine. The system is modular and consists of a pressure lens towards the leading edge of a flat roof building to accelerate the air-flow through the turbine. A control system ensures the efficient and safe use of the system and manages power output data and optimum positioning of the system features. The system is further enhanced by the inclusion of solar air collectors which heat the air for use in air-heating systems within the building.
Project context and objectives:
The overall industrial objective of the project is to develop a roof-mounted building augmented wind turbine module which will allow a small turbine to double its power output and which will also provide air heating and powered passive ventilation in the building below, cutting system payback time to an average of five years. The project will create knowledge relating to the air flow across flat roofed buildings and a model for how it can be best accelerated and channelled to achieve at least a 30 % increase in ducted air over the free air stream so increasing the power yield from the turbine. The system will be modular and consist of a pressure lens towards the leading edge of a flat roof building to accelerate the air-flow through the turbine. A control system will ensure the efficient and safe use of the system and will manage power output data and optimum positioning of the system features. The system is further enhanced by the inclusion of solar air collectors which heat the air for use in air-heating systems within the building.
The technical work period (1 February 2009 to 31 January 2011) has been spread over the tasks in the following work packages (WPs):
WP 1 - Aerodynamic research / model creation
WP 2 - Design of 'pressure lens' surface profiling
WP 3 - Design of Venturi duct
WP 4 - Design of warm-air injection systems
WP 5 - Control systems
WP 6 - Creation and test of rooftop prototype.
Project results:
The ROOF-CAPTURE 'kick-off' meeting was successfully held at UK MatRI Ltd on 26 March 2009 where partners attended and expressed much enthusiasm, agreeing that an initial concept design should be developed as soon as possible given that there was sufficient background work undertaken by three of the partners during the first two months of the project to be able to aid this process. The consortium agreed that there is a real opportunity to develop a commercial solution for small-scale wind turbines offering increased yields and that there is a need to develop this solution as soon as possible.
By month three of the project, a review had been undertaken of current state-of-the-art technologies, their respective power yields, legislation concerning the installation of small-scale wind turbines and the potential benefits for companies purchasing renewable energy systems including possible feed-in tariffs for selling energy back to the grid. It became apparent that compliance with the micro-wind certification scheme is necessary to enable installation of the ROOF-CAPTURE technology onto buildings was necessary so the consortium had to ensure that any prototype system met this standard which was achieved by selecting a turbine made by one of the partners (Eclectic Energy) which is undergoing testing to ensure compliance with the standard.
TU Delft carried out initial modelling work to determine air-flow characteristics over a flat-roof building and determine how best this can be utilised to augment the air-flow through a turbine. This work also included an analysis of the efficiencies of turbines mounted horizontally (HAWT) and vertically (VAWT). UK MatRI conducted a literature search that showed a 'wind-map' of Europe giving data on average wind speeds in different parts of this geographical area. The consortium also held discussions on the most suitable site for the prototype test as it needs to be in a good wind site and be accessible for installation and maintenance; planning permission from the relevant local authority was also a key issue to be resolved. UK MatRI was chosen as the best site within the consortium to site a prototype as there are two flat roofed buildings available so anemeometers were installed and wind data captured over many months of the project.
A prototype duct was designed and manufactured by UK MatRI for testing in a wind-tunnel at TU Delft. Testing included obtaining power output from a turbine supplied by Eclectic Energy in both free-air stream and within the duct at wind speeds ranging from 0.5 m/s to 30 m/s. These trials also included putting the power into batteries (dump load) and to the grid to determine recorded outputs. The augmentation effect from the first trials was very low and proved that the venture duct theory does not achieve the desired augmentation (30 %) over a turbine in free-air stream and at low wind speeds there is no benefit at all. The manufacturing cost of a venturi duct is also expensive so the consortium decided to explore the effect of an aerofoil and bull-nose arrangement. Further modelling undertaken by TU Delft showed that there should be significant augmentation for such an arrangement and determination of the optimum bull-nose arrangement and aerofoil shape was made through the modelling. TU Delft, UK MatRI and Eclectic Energy then went back to the wind-tunnel with a simple mock-up of this arrangement and repeated the test programme. The results showed far better augmentation could be achieved so work commenced on a design for the actual prototype testing in real world conditions.
One of the original aims of the project was to carry out development of a generator (turbine) and fan set. The need to use the standard Eclectic Energy turbine (D400) due to the constraints with MCS accreditation somewhat negated the need for this research, however, TU Delft did carry out a review of the efficiency of the fan-set by making comparisons through modelling of the wakes and vortices caused by three blade types. The standard blade used by Eclectic Energy proves to be an efficient design when compared with the others.
Point-L developed a control system using LONWORKS logic to control the optimum angle of the aerofoil, fail-safe systems (in the event of exceedingly high wind-speeds) and most importantly the capture of data regarding power outputs. The consortium decided that PV technology should be included as the technology will then be capable of harvesting renewable energy 24 hours per day from:
a) wind (from any direction and augmented when the turbines are aligned with the aerofoil);
b) sun (possible inclusion of photovoltaic panels on the bull-nose and aerofoil); and
c) solar-thermal through use of a solar-air collector.
The control system is modular and can be adapted for bespoke applications; it also has the capability to control multiple turbines and aerofoils from one control unit so keeping the cost to a minimum. The work undertaken by Point-L was supported by Brodarski who developed interfacing software for the Lonworks system.
Due consideration was given to the solar-thermal aspect of the project. The project partner Solar-venti manufacture solar air-collectors which harvest air via an air-collector which can then be heated or cooled and transferred into the building on which it is fitted to provide warm or cool air. These systems are popular in holiday cottages which can be left unpopulated for long periods so the systems serve to provide constant source of fresh air. Solar-venti worked with the consortium to provide an air-collector capable of collecting air from all faces of the panel (front, top, rear and sides) and pass the air through a two tier system of heating and out through a duct for use in air heating systems. The design of this system was made to integrate with the ROOF-CAPTURE module and placed beneath the bull-nose on the wall of the building. This system is modular as well and calculations can be made as to the number of panels required to provide warm air for any given area of building.
A great effort was made to ensure that the resultant prototype system would be feasible from a cost benefit and deliver the desired payback time of five years. UK MatRI developed a payback model that considers a number of parameters in order to determine the payback time achievable for various sites, the parameters include:
- number of turbines in the array;
- wind speed;
- power yields from the turbines;
- cost of system (derived from a bill of materials);
- cost of installation;
- feed-in tariffs.
A prototype system was designed by UK MatRI for installation onto its roof at their site in Melton Mowbray (United Kingdom (UK)). In order to finalise the design agreement had to be made on the number of turbines to be included in the prototype, the shape of the bull-nose, design and materials for the aerofoil, the ability to modify the system configuration (i.e. number of turbines) and the ease or modularity of assembly. The design was subjected to modelling to determine the dynamic and static loads being placed on the frame and roof and modifications made to the design as necessary to spread the loading evenly. The roof was subjected to a site-survey and modifications made to the roof-space beneath the system to ensure no damage to the roof could occur. Before any installation work could commence a full risk assessment was undertaken and an assembly plan formulated to ensure safety of all personnel.
The prototype system is now fully installed at UK MatRI and undergoing tests. Power output data is recorded by the control system twice a minute as is wind speed (above and below the aerofoil), wind direction and temperature inside and outside the solar-air collector. From this date, the efficiency of the system can be determined.
The collation of data is ongoing and full results will be announced once three different configurations have been tested, it is known however that augmentation of the turbines is achieved when the wind is flowing up the side of the building and over the parapet. The data can be difficult to filter for the effect of augmentation as the wind in this location swirls a lot causing many changes to the turbines position (i.e. they are not always in the optimum position). It has been agreed with the co-ordinator that the possibility of extending the planning permission will be explored in order to show potential customers a working system.
Potential impact:
The project will create knowledge relating to the air flow across flat roofed buildings and a model for how it can be best accelerated and channelled to achieve at least a 30 % increase in ducted air over the free air stream so increasing the power yield from the turbine. The system will be modular and consist of a pressure lens towards the leading edge of a flat roof building to accelerate the air-flow through the turbine. A control system will ensure the efficient and safe use of the system and will manage power output data and optimum positioning of the system features. The system is further enhanced by the inclusion of solar air collectors which heat the air for use in air-heating systems within the building.
Project website:
http://www.roofcapture.eu
For installation in the UK and other countries, please contact:
Mark Robinson on:
Tel: +44-(0)11-62779577
E-mail: MarkR@torclad.com
Project context and objectives:
The overall industrial objective of the project is to develop a roof-mounted building augmented wind turbine module which will allow a small turbine to double its power output and which will also provide air heating and powered passive ventilation in the building below, cutting system payback time to an average of five years. The project will create knowledge relating to the air flow across flat roofed buildings and a model for how it can be best accelerated and channelled to achieve at least a 30 % increase in ducted air over the free air stream so increasing the power yield from the turbine. The system will be modular and consist of a pressure lens towards the leading edge of a flat roof building to accelerate the air-flow through the turbine. A control system will ensure the efficient and safe use of the system and will manage power output data and optimum positioning of the system features. The system is further enhanced by the inclusion of solar air collectors which heat the air for use in air-heating systems within the building.
The technical work period (1 February 2009 to 31 January 2011) has been spread over the tasks in the following work packages (WPs):
WP 1 - Aerodynamic research / model creation
WP 2 - Design of 'pressure lens' surface profiling
WP 3 - Design of Venturi duct
WP 4 - Design of warm-air injection systems
WP 5 - Control systems
WP 6 - Creation and test of rooftop prototype.
Project results:
The ROOF-CAPTURE 'kick-off' meeting was successfully held at UK MatRI Ltd on 26 March 2009 where partners attended and expressed much enthusiasm, agreeing that an initial concept design should be developed as soon as possible given that there was sufficient background work undertaken by three of the partners during the first two months of the project to be able to aid this process. The consortium agreed that there is a real opportunity to develop a commercial solution for small-scale wind turbines offering increased yields and that there is a need to develop this solution as soon as possible.
By month three of the project, a review had been undertaken of current state-of-the-art technologies, their respective power yields, legislation concerning the installation of small-scale wind turbines and the potential benefits for companies purchasing renewable energy systems including possible feed-in tariffs for selling energy back to the grid. It became apparent that compliance with the micro-wind certification scheme is necessary to enable installation of the ROOF-CAPTURE technology onto buildings was necessary so the consortium had to ensure that any prototype system met this standard which was achieved by selecting a turbine made by one of the partners (Eclectic Energy) which is undergoing testing to ensure compliance with the standard.
TU Delft carried out initial modelling work to determine air-flow characteristics over a flat-roof building and determine how best this can be utilised to augment the air-flow through a turbine. This work also included an analysis of the efficiencies of turbines mounted horizontally (HAWT) and vertically (VAWT). UK MatRI conducted a literature search that showed a 'wind-map' of Europe giving data on average wind speeds in different parts of this geographical area. The consortium also held discussions on the most suitable site for the prototype test as it needs to be in a good wind site and be accessible for installation and maintenance; planning permission from the relevant local authority was also a key issue to be resolved. UK MatRI was chosen as the best site within the consortium to site a prototype as there are two flat roofed buildings available so anemeometers were installed and wind data captured over many months of the project.
A prototype duct was designed and manufactured by UK MatRI for testing in a wind-tunnel at TU Delft. Testing included obtaining power output from a turbine supplied by Eclectic Energy in both free-air stream and within the duct at wind speeds ranging from 0.5 m/s to 30 m/s. These trials also included putting the power into batteries (dump load) and to the grid to determine recorded outputs. The augmentation effect from the first trials was very low and proved that the venture duct theory does not achieve the desired augmentation (30 %) over a turbine in free-air stream and at low wind speeds there is no benefit at all. The manufacturing cost of a venturi duct is also expensive so the consortium decided to explore the effect of an aerofoil and bull-nose arrangement. Further modelling undertaken by TU Delft showed that there should be significant augmentation for such an arrangement and determination of the optimum bull-nose arrangement and aerofoil shape was made through the modelling. TU Delft, UK MatRI and Eclectic Energy then went back to the wind-tunnel with a simple mock-up of this arrangement and repeated the test programme. The results showed far better augmentation could be achieved so work commenced on a design for the actual prototype testing in real world conditions.
One of the original aims of the project was to carry out development of a generator (turbine) and fan set. The need to use the standard Eclectic Energy turbine (D400) due to the constraints with MCS accreditation somewhat negated the need for this research, however, TU Delft did carry out a review of the efficiency of the fan-set by making comparisons through modelling of the wakes and vortices caused by three blade types. The standard blade used by Eclectic Energy proves to be an efficient design when compared with the others.
Point-L developed a control system using LONWORKS logic to control the optimum angle of the aerofoil, fail-safe systems (in the event of exceedingly high wind-speeds) and most importantly the capture of data regarding power outputs. The consortium decided that PV technology should be included as the technology will then be capable of harvesting renewable energy 24 hours per day from:
a) wind (from any direction and augmented when the turbines are aligned with the aerofoil);
b) sun (possible inclusion of photovoltaic panels on the bull-nose and aerofoil); and
c) solar-thermal through use of a solar-air collector.
The control system is modular and can be adapted for bespoke applications; it also has the capability to control multiple turbines and aerofoils from one control unit so keeping the cost to a minimum. The work undertaken by Point-L was supported by Brodarski who developed interfacing software for the Lonworks system.
Due consideration was given to the solar-thermal aspect of the project. The project partner Solar-venti manufacture solar air-collectors which harvest air via an air-collector which can then be heated or cooled and transferred into the building on which it is fitted to provide warm or cool air. These systems are popular in holiday cottages which can be left unpopulated for long periods so the systems serve to provide constant source of fresh air. Solar-venti worked with the consortium to provide an air-collector capable of collecting air from all faces of the panel (front, top, rear and sides) and pass the air through a two tier system of heating and out through a duct for use in air heating systems. The design of this system was made to integrate with the ROOF-CAPTURE module and placed beneath the bull-nose on the wall of the building. This system is modular as well and calculations can be made as to the number of panels required to provide warm air for any given area of building.
A great effort was made to ensure that the resultant prototype system would be feasible from a cost benefit and deliver the desired payback time of five years. UK MatRI developed a payback model that considers a number of parameters in order to determine the payback time achievable for various sites, the parameters include:
- number of turbines in the array;
- wind speed;
- power yields from the turbines;
- cost of system (derived from a bill of materials);
- cost of installation;
- feed-in tariffs.
A prototype system was designed by UK MatRI for installation onto its roof at their site in Melton Mowbray (United Kingdom (UK)). In order to finalise the design agreement had to be made on the number of turbines to be included in the prototype, the shape of the bull-nose, design and materials for the aerofoil, the ability to modify the system configuration (i.e. number of turbines) and the ease or modularity of assembly. The design was subjected to modelling to determine the dynamic and static loads being placed on the frame and roof and modifications made to the design as necessary to spread the loading evenly. The roof was subjected to a site-survey and modifications made to the roof-space beneath the system to ensure no damage to the roof could occur. Before any installation work could commence a full risk assessment was undertaken and an assembly plan formulated to ensure safety of all personnel.
The prototype system is now fully installed at UK MatRI and undergoing tests. Power output data is recorded by the control system twice a minute as is wind speed (above and below the aerofoil), wind direction and temperature inside and outside the solar-air collector. From this date, the efficiency of the system can be determined.
The collation of data is ongoing and full results will be announced once three different configurations have been tested, it is known however that augmentation of the turbines is achieved when the wind is flowing up the side of the building and over the parapet. The data can be difficult to filter for the effect of augmentation as the wind in this location swirls a lot causing many changes to the turbines position (i.e. they are not always in the optimum position). It has been agreed with the co-ordinator that the possibility of extending the planning permission will be explored in order to show potential customers a working system.
Potential impact:
The project will create knowledge relating to the air flow across flat roofed buildings and a model for how it can be best accelerated and channelled to achieve at least a 30 % increase in ducted air over the free air stream so increasing the power yield from the turbine. The system will be modular and consist of a pressure lens towards the leading edge of a flat roof building to accelerate the air-flow through the turbine. A control system will ensure the efficient and safe use of the system and will manage power output data and optimum positioning of the system features. The system is further enhanced by the inclusion of solar air collectors which heat the air for use in air-heating systems within the building.
Project website:
http://www.roofcapture.eu
For installation in the UK and other countries, please contact:
Mark Robinson on:
Tel: +44-(0)11-62779577
E-mail: MarkR@torclad.com