Can solar panels be disastrous

The Tesla Powerwall has changed the way people talk about solar batteries and home energy storage from being a conversation about the future to a conversation about now.

In the humble opinion of this SolarReviews writer, it is currently the best solar battery and smart home energy-storage solution on the market. I would love to say it isn't (because I love to promote small independent solar companies and solar products) but credit where credit is due: the new Tesla Powerwall kicks ass.

How much does the Tesla Powerwall cost in 2020?

Back in October 2018 a price rise that brought the cost of the Powerwall to $6,700 and the supporting hardware to $1,100. That means a total system cost to $7,800 — plus installation. Given the installation price guide issued by the company of between $2,000–$3,000, that means a total installed cost of around $10,000. 

Is the Tesla energy storage solution eligible for the federal investment tax credit?

Yes, the Powerwall is eligible for the 26% solar tax credit where it is installed with solar panels to store solar power.

What 5 factors make the Tesla Powerwall solution stand out as the best current solar battery storage solution for residential energy storage?

  1. Cost at around $10,100 installed for 13.5 kWh of usable storage. This is relatively good value given the high cost of solar energy storage. Still not an amazing return, but better than its peers;

  2. Built-in battery inverter and battery management system now included in the cost. With many other solar batteries the battery inverter has to be purchased separately;

  3. Battery Quality. Tesla has partnered with Panasonic for its Lithium-Ion battery technology meaning the individual battery cells should be very high in quality;

  4. Intelligent software controlled architecture and battery cooling system. Although I am not an expert on this, it appears to me that Tesla is leading the pack in terms of controls to ensure both safety and smarter functionality; and

  5. Time-based controls allow you to minimize the cost of electricity from the grid over a day when you face time-of-use (TOU) electricity billing. Although others have talked about being able to do this no one else has shown me a slick app on my phone to set peak and off-peak times and rates and to have the battery work to minimize my cost as the Powerwall can do.

Why would someone buy a Powerwall solar battery when their utility offers net metering?

Net metering gives a credit for excess power sent to the grid so in effect this policy does economically what a solar battery does physically…it provides relief from having to pay for power when your solar panels are not producing by storing excess electricity generated during the middle of the day. Net metering is under attack from utility companies but it is still available in more than 30 states as of January 2020.

So why would you pay for a Tesla home battery when you have access to net metering for free?

The answer is a combination of three factors, which are:

  • The rise of time-of-use (TOU) electricity rate plans from utilities;

  • Government incentives in key states like California; and most importantly

  • The Tesla Powerwall now offers time-based control…and it's awesome.

Why are time-of-use electricity rate plans making the Powerwall more popular?

Time-of-use electricity rate plans are schedules of rates charged for electricity by utility companies where more is charged for power during peak times and less is charged for power during off-peak times. These plans are becoming popular with public utilities commissions around the country as a way to discourage the use of power at peak times.

You can find out if your utility offers a time of use electric rate plan that may be cheaper for you.

The difference in pricing can be significant. For example, on the cheapest PG&E rate plan during the summer months the off-peak power charge is $0.26 cents but during peak hours the charge is $0.36 cents. This type of billing by utilities will become more and more common and already in California time-of-use billing is now mandatory for residential customers of investor-owned utilities as of 2020.

Is Tesla Powerwall the best solar battery?

Put simply, yes — because none of the other mainstream home energy storage solar batteries offer time-based control of charging and discharging (or at least as elegantly as the Powerwall does).

The Powerwall allows you to set into the app on your phone that controls it the peak and off-peak times and rates of your utility. It will then use both excess solar power and grid power to make sure the battery is fully charged at the end of off-peak times so that you can use as little power as possible during the expensive peak time. Kudos, Tesla engineers...kudos.

What is the Tesla Powerwall lifespan?

The system has a 10-year limited warranty but may last longer. The use of Lithium-Ion batteries for home power storage is quite new and some suggest the battery chemistry may not even last the 10 year warranty period.

What is the current Tesla Powerwall availability?

It is really hard to get your hands on a Powerwall at the moment with wait times of between 6-9 months. If you want one installed with your solar panels then it is best that you arrange to buy both the Powerwall and your solar panels for home now. You can use our solar calculator to get a free online cost and savings estimate for your home and get the ball rolling.


What incentives are available to include the Tesla Powerwall home battery with your solar system?

In preparing this article, I attempted to use the incentives database but it was hard to find any definitive list of solar energy storage or solar battery-specific incentives. The difficulty in this research lies in the fact that energy storage may or may not be eligible for energy efficiency grants, tax credits or rebates for which there are literally thousands of programs around the country.

Given this complexity, our suggestion would be to reach out to local solar companies as they will usually know all the local incentives available. You can get an online solar savings estimate through Solar-Estimate.  

How much power does the Powerwall 2 battery provide?

The Powerwall has a storage capacity of 14-kilowatt-hours (kWh) of electricity, of which 13.5 kWh is usable.

Will the Powerwall 2 save enough money over its life to justify the cost to buy it?

Most experts say the average American household can break even by purchasing the Tesla Powerwall 2.0. On average, U.S. homes consume approximately 28 kWh per day, meaning the typical Powerwall 2.0 provides the perfect amount of storage to deal with nighttime electricity use.

How many hours of backup power will the Powerwall storage system give me in a blackout?

Practically speaking, the length of time the battery will last depends on a host of variables, including how much energy was stored and how much power you use.

What am I covered for if the battery fails?

Tesla's 10-year warranty guarantees it will store at least 70% of its rated output over the 10-year period. It assumes the system will store electricity daily and discharge it regularly.

Is the Powerwall 2 worth it for your home?

For the vast majority of us that do live in states with net metering laws, solar plus storage makes no sense. Storing energy in battery packs is not necessary because net metering allows you to bank credits for your excess solar generation during the day to use to buy power at night. It allows homeowners to economically store electricity for solar arrays rather than physically store it. For those with access to net metering, you should buy solar panels in 2020 while you can get the 26% federal solar tax credit and before net metering laws end.

Why should I buy solar batteries for my home even though the investment return doesn’t stack up?

Clean energy, whether wind or solar, are intermittent by nature. This means the development of energy storage solutions is crucial for our society to move towards being powered by 100% renewable energy — and save the planet from the disastrous effects of climate change.

Tesla the company — and its founder Elon Musk — are doing more to combat climate change than any other company in the world. Tesla Energy built the world’s largest energy storage battery in South Australia using Tesla Powerwalls. The Tesla Motors division is also doing massive things to make electric vehicles a reality for everyday American families and the Tesla Model 3 has brought the price of a luxury electric vehicle within the reach of tens of millions.

See how much a solar-plus-battery solution will cost for your home