Proven Engineering Products Ltd. is a mechanical engineering company with facilities for machining, welding and plastics formation specialising in renewable energy sources. The objective of the project was to improve the human interface and control features of the well established wind turbine system for off grid power supplies with micro-controller technology. The introduction of microcontroller technology will enable a gain in market share and the knowledge transferred into the company to allow further development and new products. The applications for wind turbine system are in remote houses and farms, telecommunication sites, etc. both in the UK and world-wide for the generation of off grid power.
The renewable energy market is growing, and in order to sustain growth and competitiveness, Proven needs to make its wind turbine system more user friendly; more capable and adaptable, and to provide customisable features for the growing market. Our present system is not customisable and requires costly factory set up procedures of many potentiometers and other discrete components. The user has a tendency to modify the settings in the field which most often require the unit to be returned for "calibration. With the micro-controller controlled system set up procedures for the user to operate can be included and Proven expect to gain market share by supporting extra features. There is also an emerging market from the industrial sector that demands extra features from such equipment that must be customisable from installation to installation. This can only be done by the use of electronics more advanced than discrete components. This represents a major leap in technology for Proven Engineering Ltd. who are a mainly mechanical engineering company.
There are two main types of wind power systems. The first is a simple system which supplies a simple load for water heating for example. In the second more complex system the wind turbine charges a bank of batteries whose dc voltage can then be converted into domestic 230V ac power. Presently the present system requires two systems, however, with the microcontroller system both types can be incorporated on the same board and even integrated to work together where appropriate.
A user interface via a keyboard and LCD status display is included in the new microcontroller system. The existing system provides only very crude load control with difficult to use and adjust analogue monitoring circuits. There is no friendly user interface either for the input of information or for display.
The cost of the experiment was ECU 47k and was scheduled to last for 14 months. The duration of the actual project was 18 months, Several issues contributed to this delay which including the illness of the main engineer on the project and some technical issues with the project.
The payback period is estimated to be within two years assuming the sales increase as shown in section 4 and the ROI is estimated to be 400% within a five year period. However, the microelectronics unit only represents 5% of the selling price of the completed wind turbine system and the relationship between this project and increased sales is complex. Since it is a part of a system in a developing new market - the project will both increase sales due to better functionality and user benefits and making it easier to produce in the increasing production needs.
As can be seen from the figures below in 17, we expect to double our sales next year and increase thereafter - based on actual orders and enquires - so increasing both turnover and profitability.
There were many lessons learned during the project, with perhaps overcoming the fear of new technology with help and support being the greatest; and the choice of micro-controller that best suited the expertise of Proven and the application. There are perhaps lessons to be learned for the microcontroller industry as well - more work needs to be done to enable small non-electronics companies like Proven to easily assimilate and use microcontroller technology in their products.
Another major lesson was the need for detailed planning at the start of the project and accurate monitoring throughout the duration of the project.
There are several routes to economic benefit from the project.
- Reduction of overall system cost.
When an integrated inverter module is included there will be a significant ( ECU2500 )reduction in system cost so making sales easier in a capital cost sensitive market. This will also allow in house manufacture of more of the system rather than import from the USA.
- Reduction of circuit board stocks.
Presently two very different boards are used with different assembly and set up needs. The microcontroller system will have only one board for all functions. Combined with the increase in sales this will for the first time allow sub contract board manufacture in economic batches so cutting costs and improving quality.