Energy storage is becoming a hot product in corporate energy procurement, with everything from solar paired with energy storage to stand-alone storage systems on companies' wish lists. The market is still small, but it's growing quickly, and as companies consider their procurement plans for the future, we should see more growth in 2019 and beyond. 

As much as energy storage may be important for making large amounts of renewable energy work effectively in the grid, the reason companies are investing in energy storage is all about the bottom line. There's real financial justification for energy storage, and that's what keeps the business going. 

Rendering of an energy storage facility with wind turbines in the background

Image source: Getty Images.

How energy storage makes money

Energy assets like energy storage need to make financial sense before companies deploy them at scale, and it's not a slam-dunk that energy storage meets the minimum return on investment. Still, there are a few ways energy storage can make financial sense both through cost savings and revenue from the battery's value to the grid: 

  • Demand charges can be up to half of a commercial building's energy cost and are based on the peak amount of electricity demand going to the building. So, a big spike in demand for 15 minutes for one hour a month can mean thousands of dollars in added costs. Energy storage can help reduce those peak demand numbers and therefore save customers money. 
  • Virtual power plants are a relatively new concept in energy, and what they're essentially trying to do is band a group of energy storage assets together to act like a much larger power plant. When they work together, they can offset the need for expensive peaker plant power by using up cheaper electrons generated in off-peak hours. Utilities are starting to pay companies like Tesla (TSLA -3.67%), SunPower (SPWR -47.95%), and Sunrun (RUN -1.52%) for their virtual power plants, adding value to the energy storage they put into buildings. 
  • Backup power is a more intangible benefit, but companies who rely on electricity to keep operations going definitely put a premium on having a quality backup, which energy storage is perfect for. 

These aren't the only ways energy storage can add value to companies or the grid, but they show the biggest selling points. When corporations are looking at their energy needs, energy storage can be a lot more appealing when you consider the cost savings, revenue potential, and value in backup power. 

Who's making money off energy storage?

How do investors capitalize on the energy storage growth trend? Battery makers are in a tough position because they are in a commodity business and rarely develop energy storage projects themselves. LG Chem (NASDAQOTH: LGCLF) is one of the largest battery manufacturers for energy storage, but it still only holds a fraction of the market. And it relies on third parties to install and control the energy storage system. 

In the commercial market, SunPower is the biggest name in solar, and it's adding energy storage to about 30% of its commercial solar installations. As the cost of batteries comes down, I expect the level of energy storage penetration to go up and SunPower to be able to find more ways to monetize its energy storage installations, which are often built on the company's balance sheet. 

Tesla is another leader in energy storage and may be playing more of a supply role than SunPower. It's the battery manufacturer at the Gigafactory, and it's selling Powerpacks to commercial buildings, often through projects developed by someone else. But it has the scale to make this a very big business going forward. 

Most of the other companies in energy storage are private, like Stem and Sonnen, who have built large energy storage businesses. But they haven't hit public markets, and we don't yet know if they're making money on commercial energy storage. 

The size of the energy storage market

In the U.S., energy storage installations were 311 MW and 777 megawatt-hours in 2018, up from virtually nothing just six years ago. About a third of the installations so far in 2018 are commercial storage projects, and the segment has shown more stable installation trends than residential or utility-scale storage. 

Still, the industry is just getting started, and Wood Mackenzie and the Energy Storage Association's analysts expect total MW hours deployed to grow nearly 14 times in the next five years. Commercial energy storage will be a big piece of that growth, so you can see why companies are so excited about it.