The Convergence of Renewables, the Smart Grid and (Maybe) PV Inverters

Photovoltaic inverters could be the smart grid portal to the home.

There is an entrepreneurial and venture capital rush in building out the Home Area Network (HAN).  Companies like People Power, Tendril, Google, Cisco, iControl, Lixar (bought by Gridpoint), Greenbox (acquired by Silver Spring Networks), Control4, EnergyHub, EcoFactor, et al. are all working on software and hardware pieces of home and building energy management.



The millions of deployed smart meters tend to look out towards the utility.  When these meters interact with the appliances in the home, they typically work through some hardware and software gateway; one that is armed with wireless capabilities and intelligence on household behavior. 

What if there was already a piece of home electronics that contained some intelligence on energy usage, was connected to the grid and had some communications capabilities? 

Startup iControl already has a piece of hardware in the home in the form of a home security product.  They don't have to worry about the high cost of customer acquisition -- they already have a customer.  Their ambitions of moving into the smart grid space seem logical and intuitive.

But there's another piece of electronics starting to appear at the home that might also have a head start as the gateway to the HAN -- solar inverters.



Enphase is not be limited to the DC to AC microinverter function, and apparently never intended to be.  The company's CEO, Paul Nahi, hinted at their grander ambitions at Greentech Media's Solar Summit in Phoenix last week. (BTW -- last week was a good week for Enphase.)

Nahi spoke of "Their Energy," the utility's domain, and "My Energy," the energy generated and consumed within the four walls of the home. That's where Enphase expects to play -- and where other microinverter firms like SolarBridge are considering a market entry.

Enphase, like other HAN dashboards, envisions a product that provides control over generation and consumption with a simple web-based interface leveraging their existing microinverter, internet gateway, energy monitoring services and powerline communications.  Nahi sees the product as granular -- the right size for the customer, resilient, and providing plenty of actionable data.

Greg Madianos, Product Line Director at microinverter manufacturer SolarBridge, said in an email: "We firmly believe that inverters will play a central role in enabling the smart grid to incorporate large quantities of distributed generation.  Not only as an abstract concept, but with specific command-and-control functionality in mind for allowing sophisticated management of power factor and reactive power, for example, while also (at the other end of the spectrum) informing a homeowner of how much power the PV array is producing relative to the homeowner's overall usage as a means of moderating consumption."



There are other inverter companies looking for "grid awareness" and grid integration, such as PV Powered and Advanced Energy.  We reported on microinverter firm Petra Solar and their utility grid monitoring capabilities here.  And at the utility scale, inverter firms like SMA, Satcon, and GE incorporate features like low voltage ride through (LVRT) and the ability to compensate for reactive grid power.