1 _ INTRODUCTION

 This project implements an original concept for heating a buiding all over the year, simply using wind power and solar energy. The purpose of this blog is to present quite in depth the design, the concept and the preliminary sizing calculations.

The main idea is to use windpower to mechanically stirr a large quantity of water continuously as soon as the wind blows. A complementary contribution comes from a large number of solar heating panels. The autonomy is brought-in by a huge seasonal tank of water integrated in the basement of the building.

A windmill is used to actuate the stirrer. Contrarily to classical wind-machines generating electricity, a high rotational speed is not required in that application. Instead, a high torque is necessary. So the windmills that are still used to pump water from the water-table in remote farms are particularly well suited. A side-consequence of this choice is that the blades of such windmills do not require sophisticated profiles and are very easy to manufacture. The windmill used in this project is 5-meters in diameter and counts 30 blades.
The stirrer is constituted of 8 mobile flat paddles rotating against 8 fixed flat paddles. It is located just below the windmill. It is around 1.5-meters in diameter and 3-meters high. The level of water in the stirrer is made variable, so that the resisting torque on the shaft of the windmill is continuously controlled, and the yield of the system continuously optimized.
The water-tank in the basement of the building is huge (720 cubic-meters). It is thoroughly insulated by a 1-meter thick polystyrene wall all around.
The building is of octagonal section 20mx20m with 4 or 5 storeys. The roof includes a large flat surface with a slope oriented full South. It is equipped with around 160 square-meters of heating solar panels and three photovoltaic panels of 21 square-meters each .

Although the design is made so that all the components (mainly the windmill and the stirrer) are very low-cost and easy to manufacture, it appears quickly that it could be a lot easier and more economical to heat such a building using only solar energy.
It is the reason why this solution is more adapted for northern (or southern) countries with high latitudes where the daylight period is very short in winter, where the insolation is poor and where it is cold enough to justificate such an implementation. Countries like Scotland or Denmark are also known for very high winds all over the year on their west coasts: they are natural candidates for this solution. Remote places away from the electrical grid or other fossil energy networks are all-the-more well suited.

This solution cannot be universal and is limited to a niche-market.

I am looking for partners to finalize the design and then implement a demonstrator in a suitable environment.