The solar dryer presented is an alternative for drying woodchip in Scotland. Dryer and solar collector are parts of the solar dryer and have been presented and analysed separately. Woodchip drying performance has been described for certain conditions in a range of low temperatures, relative humidity and low drying velocities. Concluding that increments in either flow rate or drying temperature reduces the drying times. Page model has been found to be a simple and accurate model that describes with good agreement the moisture content curves as a function of drying velocity and temperature.

The solar thermal system presented is a particular prototype based on the transpired plate collector. The connection between PV-panel and fan comes to a low threshold irradiance that allows the system works in poor light conditions. The thermal system increases considerably the ambient temperature in all the range of irradiance and delivers flow at high temperatures with high efficiency at high irradiance levels.

In future work, in order to optimize the solar collector performance, the configuration of the collector may be modify: hole distribution of the absorber, material employed, the using of glazing cover. Once dryer and thermal systems are completely assessed, it will be possible to draw main conclusions about using solar energy for drying woodchip in Scotland.

References

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