Tesla announced an entirely new product line yesterday that, surprise, was not a car. Owner Elon Musk showcased Tesla's new push into home power storage with the unveiling of what is called, "The Powerwall." Essentially, it's a large $3,500 home battery that homeowners and businesses can use to store excess power for use when they need at a later time. This ultimately provides savings on energy costs.
As Elon Musk put it during his presentation, this product may have the potential to, "fundamentally change the way the world uses energy, at the extreme scale." However, before that becomes a reality, and considering this is an entirely new market for Tesla to be entering, there will obviously be speed-bumps as this technology progresses down the road into mainstream use. Just as Teslas are hard to spot on the road today, Powerwalls will be tough to spot in the garage. Let's take a look at a list of some immediate concerns and benefits that comes to mind:
1. The life span of the battery itself. After what period of time will owners have to replace the battery due to the diminishing returns on efficiency? Over time, the battery will lose efficiency and each charge will add less and less power to the battery. Think of the first charge you get on your new phone compared to one year into use. If you find yourself constantly having to charge your phone, that's because the battery inside has lost a portion of it's energy capacity. The same would hold true of this home battery. Tesla is offering a 10 year warranty on the product, so I'm assuming that they will replace the battery for free during that time if any issues arises. So $3,500 may be good for at least 10 years.
2. How much money will this actually save the consumer? The average cost of electricity in the US is somewhere around 10-12 cents per kWh. If your house consumers 1000 kWh per month, you're paying a little over $100. That's $1200 per year in electricity. So, even if you can sell back electricity to the utility companies, installing a battery and solar panels on the roof still costs many times what you would be saving. The building of the Gigafactory is one way Tesla is going to bring down installation costs, but until there are substantial improvements in cost reduction on both products (or further tax subsidies), these products are only possible for a select market. It is just not economically feasible for the average American household.
3. Environmental Benefits. This could potentially save large amounts of waste energy that is produced on the grid. Power plants have no storage capacity, and a power plant is constantly cranking out energy. If demand is lower than supply, that excess energy is being wasted. However, if there is a place to store that energy in batteries, this energy can be used later at night or some other date. Thus, energy is being used more efficiently.
4. Backup Power. With Hurricans and large storms becoming more and more frequent, the need for backup power will increase. Can batteries take the place of what gas generators provide now for those worried about losing power during a storm or blackout?
5. Efficiency for Utilities. Is it possible utility companies put up some capital to have these installed in residential homes? Thus, instead of drawing power from the grid during peak hours, homeowners or the utility company could draw energy out of the batteries. There would be less strain on the energy grid as there is less demand on "just in time" energy delivery. This would be a way in which both utility companies and homeowners could save, as the cost of electricity is more expensive both to consumer and produce during peak usage hours, so a reduction in usage during peak hours is a benefit to both.
Overall, this is a great step in the direction of a sustainable future. It's not hard to imagine a world where each home has the ability to generate electricity from the sun and store excess during the day with the ability to use that stored energy at night or during cloudy days. A world of renewable, off the grid energy, that is freely captured from the sun. I do like the sound of that.