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Visualizzazione dei post da Agosto, 2017

Tesla Powerwall II - Is it worth it for my use case?

Immagine
Introduction
We have installed a photovoltaic system about one year ago, and have been logging solar production and house energy consumption since.
As of this month we have enough logging data to start looking into the economic value of adding a storage system, specifically the new Tesla Powerwall in order to improve the auto consumed amount of energy.

TL;DR: It's not worth it, yet :)

Background - Photovoltaic System Our photovoltaic system is composed by 24 Viessmann Vitovolt 300 Panels@250Wp, for a theoretical peak power of 6kWp.
The system is installed on our rooftop, and is Oriented in a W-SW configuration (Azimut@237 Degrees) with a 28 Degrees inclination, located in Northern Italy.



As it can be seen by the lower production numbers of two panels, we have a chimney that casts an important shadow on two panels (1.1.9 and 1.1.10), and we have some shadow cast by some huge trees on a neighbour's property that basically block solar radiation from 6PM onwards from spring to aut…