Making microgrids operate more efficiently can rightly be considered a clean technology innovation, even if the technology is largely being put to use in the oil industry. That's what Houston-based FlexGen Power Systems is known for, and what the company recently raised a funding round to do.

FlexGen, a startup that makes power conversion devices and the software to stabilize islanded power grid generators, has raised $2.65 million of a $7 million funding round, according to an SEC filing.

FlexGen last raised money in 2015, when it landed a $25.5 million Series A investment led by Denver-based Altira Group and the venture capital arms of General Electric and Caterpillar. Back then, CEO Josh Prueher told the Houston Chronicle that the company’s hybrid power system was being used at seven wells for three different operators, with contracts for 60 more rigs for nine large shale gas operators.

FlexGen’s Adaptive Control Technology platform comes in a cargo container and installs at off-grid sites, including areas owned by the U.S. military and oil companies. Its power conversion products, including silicon carbide power converters, can operate on their own and with energy storage to provide power quality and stability, controlled through software that monitors island grid AC or DC bus voltage, current and frequency at tenths-of-a-millisecond intervals. 

Keeping microgrid power stable requires a fine-tuning of generation and loads to manage the lack of inertial stability provided by big power plants. This is particularly important, and a number of companies have built specialized combinations of technologies to handle this challenge. One, ABB’s PowerStore, uses flywheels plus batteries and generators to back up both off-grid industrial operations and large-scale solar farms in Australia. 

Tendril and People Power keep the home energy fires burning 

Startups Tendril and People Power have been around since the heyday of home energy management about a decade ago, when companies were garnering tens of millions of dollars in investment from venture capitalists and utilities. As evidenced by our coverage since then, the market has yet to blossom into a hugely profitable business, unless you count Nest thermostats. 

Even so, Tendril has managed to keep its hand in the game, albeit not without some near-death moments, emerging from utility pilot project limbo into ongoing work with partners such as Duke and American Electric Power, NV Energy, PPL, Alliant Energy and Fortis. And while Tendril's primarily focused on delivering relatively simple home energy reports, it’s also continued to refine its data analytics capabilities, with an eye on turning homes into more predictable, flexible grid resources. 

The company also raised more than $100 million in investment, most recently with the close of a $5 million round, according to this SEC filing. Tendril previously raised $20 million from SunPower in 2014, and $25 million in 2012 from investors including GE and Siemens.  

People Power has had less public success with its approach to the smart energy market. The Redwood City, Calif.-based startup launched as a home energy software platform provider, albeit with its own range of smart thermostats and gadgets. It then shifted to seeking home appliance and office equipment partners, such as cable and power strip manufacturer Monster.

Now People Power calls itself a comprehensive IOT solution for service providers and manufacturers, via its Presto and Virtuoso platforms. Apparently this iteration of its technology is getting some interest from utilities. Earlier this month, People Power announced an additional $4 million in Series B-1 financing, bringing its total capital raised to date to $14 million. The new financing includes $2 million from innogy SE, the new subsidiary of German energy giant RWE, and $1.2 million from Origin Energy, Australia’s largest energy retailer.

Building the energy IOT for the small-commercial building sector

Speaking of IOT, startup Riptide IO announced last week that it has raised $1 million in additional financing, closing a $4 million round first launched in 2014. The Santa Barbara, Calif.-based startup was founded in 2012, and last year launched its platform to control lighting, door locks, refrigeration, and heating and cooling in small businesses. 

The small commercial sector is a tough market for energy management services, requiring technology that’s cheap and simple enough to work in a fast-paced restaurant or retail environment, and scalable enough to cover hundreds or thousands of sites. Riptide claims its system can be installed and operated with little or no training, and is “affordable for even the most modest small-business operating budget.” 

Competitors in this space include existing HVAC and power controls vendors that are building more intelligence into their devices, demand response providers like EnerNOC, startups such as Powerhouse Dynamics, GridPoint, EnTouch and PlotWatt.