Three years after acquisition of SolarCity, Tesla has made significant progress in the development PV products, as evidenced by the growing interests on the market in its energy storage system Powerwall, according to the study of EnergySage.

A major problem, however, has been Tesla's insufficient capacity for Powerwall, making it unable to meet demands.

Powerall ranked second place on the PV energy storage market in 2018, trailing only LG, as 55% of installation specialists reported receiving request for installing Powerall, although only 12% of them managed to meet the demands, according to a survey of 870 installation specialists conducted by EnergySage. By comparison, the corresponding rates of LG reached 25% and 32%, respectively.

The phenomenon also underscores insufficient inventories of installation firms, especially for popular brands. Despite their favor of Powerall, consumers often have to choose other brands, as Tesla cannot produce sufficient amount of PV cells, due to allocation of most capacities to the production of Model 3.

In a recent conference call on the company's financial statement, Elon Musk, CEO of Tesla, reported that in 2018, the company had to switch some production lines to produce auto batteries, in order to increase the output of Model 3. However, Musk is upbeat on the long-term outlook for its energy business, saying its growth rate will double that of auto business.

In a letter to shareholders, Tesla reveals its plan to increase the output of its energy storage devices, in order to double the installation volume to 2 GWh in 2019.

(Collaborative media: TechNews, first photo courtesy of Tesla website)