Tesla has offered home solar panels and Powerwall batteries for years, but starting next week the two will no longer be available separately.

Elon Musk made this announcement on Twitter (as he often does), confirming that the two products will only be sold as "integrated products." In other words, if you want solar panels, you have to buy the batteries as well.

According to Elektrek, Tesla has already stopped selling solar panels and solar roof tiles without purchasing the Powerwall. Meanwhile, Tesla's solar setup page warns that the Powerwall is not available without solar panel products. [There are several ways to look at this news. The first is that forcing customers to add battery packs will have a significant impact on the cost of installing solar panels for home use. While solar panels themselves have come down in price significantly over the past few years, batteries are still quite expensive. [Especially large ones like Tesla's Powerwall, which have a usable capacity of 13.5 kWh and currently cost $7,500 each. This does not include installation or gateway costs.

At the same time, however, there are many advantages to connecting a battery pack to a solar array. First, it means that energy can be stored during the day and reused later. This is essentially free electricity, which would normally be wasted if it were automatically fed back into the grid.

Similarly, if the main power supply is lost, the battery essentially becomes a backup power source for the home. Tesla claims that the Powerwall can provide up to 12 hours of backup, which can be extended further if connected to solar panels. How long depends, of course, on the power generation capacity and the current weather conditions.

Musk further tweeted that for new installations, the Powerwall would be placed between the solar panels and the house's electric meter and breaker panel. This ensures that the energy produced by the solar panels is first sent to the battery and not to the grid, where it can no longer be used.

Existing Powerwall owners will receive a free software update later this month.

So if you were planning to install a Tesla solar system, you will need to consider the additional cost. This is assuming you were able to install the solar system in the first place. Apparently, Powerwall is the most popular household battery, so popular that Tesla is having a hard time keeping up with demand.

Whether the new mandate will have any impact on this remains to be seen, but we have our doubts. Solar panels and household batteries are a perfect pair, and without one or the other, they don't make much sense. That is, of course, if you have the money or credit to pay for them.