Galileo was right, the generous sun has always created the finest winegrowing regions in the world, and for many years, we wasted much of that great generosity. Due to technological shortcomings and a certain inertia lurking amongst our day-to-day work, we totally depended on electricity supplied from outside Herdade do Esporão, from the very beginnings of the company until 2013. However, the opportunity for was staring us in the face. Those who visit the forested area on the south side of the estate can see the reservoir wall on their return to the wine tourism unit. And, at that moment, it dawns on them.
A matter of electrons
Most of us either never had or cannot remember the physics classes where the teacher explained how light is converted into electricity. Well, simply put, light has a unique characteristic, which is being both a wave and a particle at the same time. These units of light are called photons and are able to increase the energy in particular materials which, after a certain amount of photons – those light-wave particles -, release a small particle with electrical properties, called the electron. This has a negative charge and is attracted to surfaces with a positively charge, which, when making the transition to that surface, creates a variation in potential between the two surfaces – which was stimulated with photons and generated the electron and the positive layer that attracted it. This agitation between two layers, which act as opposite poles, generates continuous electric current that, when it passes through an inverter, is transformed into alternating electric current, ready to be stored in a battery or used in a conventional electricity network. In the same way vines and olives turn the sun (along with water and carbon dioxide) into sugar, electric-solar panels convert light… into other forms of light and movement.
A sunny day at Herdade do Esporão
In 2013, we installed the estate’s first solar panels at the Caridade reservoir wall. The 865 panels covering an area of 720m2 provide peak power of 100kW, with annual production levels of 180 kWh. After the results of 2013, there was only one thing to do – invest further. In August 2014, a second set of solar panels was set up, this time at one of Esporão’s most iconic places – the winery. The south-southwest orientation and ample space was ideal, leading to the installation of almost 1900m2 of electric-solar panels that provide peak power levels of 250kW, which is reflected in a return of over 440 kWh annual power. What is the impact of this investment in solar energy? Today, we are 50% self-sufficient when it comes to electricity use, and we want to improve these figures.
The sun that made Galileo’s grapes golden
Galileo could rest easy, Tuscany’s sun would still have all the time in the world to gild and paint the grapes he contemplated and the many more that would grow in the centuries to come. The sun has that power to transform and provide bounty. In the case of Herdade do Esporão, we can see that this investment has been very positive, financially speaking, and demonstrates that sustainability is a management philosophy and not just something one adds to give a little more colour or taste. Every day, when the sun rises and makes its way around the estate, you can hear the electronic murmur of our panels, the tone of which varies with the seasons but forever remains to encourage us to steadily advance on the solar path.