What makes a home its own micro grid?  It takes the following (and presumes that the utility has smart meters and the complex systems in place to support a two-way flow of electricity and communication):

• An alternative energy source of electricity production like solar panels on your roof
• An energy storage capability – the home battery
• Internal communicating technology that has contact with all appliances that use electricity – could be a wired or wireless technology
• HEMS (home energy management system) software that manages home electricity use and communicates with the preferred utility in real-time about pricing and billing

Let’s talk about the micro grid’s home battery.  This is an energy storage device that doesn’t look like the batteries in a flashlight.  Based on today’s technologies, it will be much bigger – say the size of an average refrigerator – that will evolve over time into a more compact unit (remember the incredible shrinking cell phones?)  It can store the cheapest energy – whether you create that through your own generating capacity or buy electricity from the utility at the lowest price point.  It kicks into action based on the agreement you set up with the utility.  You might voluntarily disconnect from the utility grid when electricity is expensive to purchase or when your generating capacity can handle your home load.  The utility may ask you to disconnect when this type of demand response program eliminates the need to fire up a peaker plant, or to mitigate the loss of transmission or distribution capabilities due to planned or unplanned events (maintenance vs. accident).  Your home is its own “island”, which is a term used by utilities to describe this distributed generation concept.  How long your home remains islanded from the larger grid is based on your utility agreement as well as you home battery duration, your management of that stored energy, how much electricity you can continue to generate on your own, and the cessation of conditions that caused the utility to island your home.

I like this entire concept, but want to emphasize that the battery needs to be managed by the HEMS system.  I want the home battery management system integrated to my HEMS software so that I have one terminal (internet-enabled TV, computer, whatever) that tells me the health of my home battery, how much capacity it has for energy and power (its duration), how long it will take to fully recharge again, and recommend if I should buy power from the utility to recharge it (and at what cost) rather than use my own generating capacity.  Thus when it is nestled in a standard home utility closet or garage, it must be regularly updating its status with my HEMS software so I don’t discover that the battery isn’t working properly during a power outage.     

Energy storage is a key component of the smart grid whether we’re talking about utility-scale storage or home-based storage.  The simplicity by which any energy storage solution is managed is a key contributor to its adoption rate by homeowners – especially those of us who like plug and play instead of interpreting technical installation manuals. 

There is a lot of conversation about whether or not the home battery drives away every morning – is it an electric vehicle (EV) or plug-in hybrid electric vehicle (PHEV) instead of a stationary device.  That’s the topic of next week’s blog. 

And now?  There’s a trend to distributed generation, evidenced in homeowners installing alternative energy solutions like solar and wind to offset at least some of their electricity needs.  Those numbers will certainly grow when Feed-In Tariffs (FITs) are in place in more states.  FITs require electric utilities to buy back excess electricity from individuals or businesses that have their own means of generating electricity from alternative energy sources.  The onset of smart meters helps the growth of distributed generation since these meters ostensibly can handle the ebb and flow of electricity.  However, a big obstacle to widespread adoption of distributed generation lies in the software that tracks and monetizes the electricity flow. 

The electric meter on your home or business is the cash register for a utility.  The billing software that calculates charges and sends out your monthly bill is usually a hairy and gnarly application that is modified only with great care and caution.  It may have to work with many different price models.  It may interface or integrate to other utility software applications for customer service, trouble tickets, and outage management.  Therefore, consider the time and effort involved for utilities to revise their existing systems (or take the risk of scrapping them for a new suite of integrated applications) to accommodate additional calculations to not only charge you for your use of their electricity, but pay you for their use of your electricity. 

Its quite a task, and possibly one without comparison.  My wireless carrier, landline provider, and cable TV provider are not set up to “buy back” unused time or channels (although I would love to stop paying for bundled cable channels I never watch), and the best deal I can find is that I get 5 cents off my grocery purchase for each bag I bring to use when shopping at my local stores.

Think about what billing software looks like to support distributed generation and FITs.  It has to interface with all other existing systems, and it has to have an interface to each participating homeowner or business.  That interface has to be real-time and hold historical data for look-backs that could range from yesterday to this day last year.  The complexity and amount of information is best managed by a web-based solution, so that homeowners can log in at any time from any computer to view their account.  Information has to include the pricing plan(s) for customers who sell back electricity, and visual displays of current flows – is the electricity flowing from utility to home or vice-versa?

Then think about what this means for the customer support operations in utilities.  People call now with questions about their bills.  There will be a huge increase in calls to utility customer service centers once distributed generation and FITs are more widely adopted.  Some of that volume is a learning curve issue and a percentage of calls will of course decrease over time, but invariably, homeowners will call in to question why their solar panels are not generating as much electricity as they think they should to trim their utility bills.  These calls really should go to the solar manufacturer, but if consumer behavior is true to form, the first call is to question the accuracy of the billing statement. 

Savvy Home Energy Management System providers (HEMS) have an opportunity to become the utilities’ best friends by reporting not only the energy consumption within a home, but also the energy generation in that home.  The ability to integrate to any manufacturer’s PV, wind, or other alternative energy system and report on performance (plus diagnostics for routine issues) can significantly impact the operational costs for utilities’ customer service centers. 

Distributed generation is going to be a big part of the Smart Grid evolution, and there will be lots of opportunities for strategic partnerships between energy producers and energy management solution providers.  Utilities could and should be encouraging these partnerships because it will make their jobs easier, and keep their customer service costs down.