Here’s a list of 13 startups that we covered last year that I would keep an eye on in 2013. A couple of these, like Opower and Nest, I also included on my list last year:

1). Stem: Formerly called Powergetics and founded in 2009, Stem‘s software tracks and analyzes energy use in buildings and helps companies predict and control their energy budgets. In addition, the company helps buildings owners tap into installed battery farms to use stored energy when grid electricity is expensive. The company got a new CEO and announced its first customer — InterContinental Hotels — in San Francisco in 2012.

2). Opower: I’ve covered these energy software leaders closely, so I won’t rehash them here. But in 2012 the company made strides like launching smart thermostat utility software trials with Honeywell, and it helped customers collectively save 2 terawatt hours of energy by the end of last year.

Honeywell & Opower’s iPad smart thermostat app

3). AutoGrid: A newbie launched by some progressive former utility execs at PG&E, AutoGrid is working on an Amazon-style recommendation engine for utilities’ energy data. Its Energy Data Platform (EDP) can take petabytes of grid data — both structured and unstructured — and crunches it to predict and analyze what is happening on the grid in real time. The company is backed by Foundation Capital, Voyager Capital and Stanford University.

4). Nest: While most people think of Nest as a smart thermostat maker company, some of the startup’s powerful innovations are the analytics that collect energy data and train the thermostat to learn your habits and shave off energy when it works for you. That data will also be valuable to utilities in some respect. Nest launched its redesigned thermostat in late 2012.

5). Viridity Energy: Viridity Energy has been around for awhile, and it uses energy data to create a new type of demand response service, or the process when utilities connect with building owners to turn down a building’s energy consumption. In 2012, Viridity got a large round from Japanese giant Mitsui. (photo of Viridity Energy SVP Western Regional Division Laura Manz)

6). EcoFactor: EcoFactor is like the service version of Nest (without the designed hardware) and is working with utilities and service providers like cable companies to manage connected thermostats in real time. In late 2012, EcoFactor raised another $8 million from Aster Capital, Claremont Creek Ventures and RockPort Capital Partners.

7). Bidgely: Launched in late 2012, Bidgely has created algorithms that can dig into real-time smart meter energy-consumption data, can reduce consumers’ home energy use by between 4 percent to 12 percent, and it can also deliver other beneficial home services to consumers. The company is backed by Khosla Ventures.

8). Space-Time Insight: Fremont, Calif.-based Space-Time Insight develops geospatial analytics around sectors like electricity, oil and gas and transportation. California’s Independent System Operator deployed the company’s software to power a control room featuring an 80-foot screen that displays map views and real-time information about energy infrastructure. The company raised a series B round of $14 million last year.

9). PlotWatt: Like Bidgely, PlottWatt has developed smart algorithms that can crunch energy data down to the appliance level to determine which of your household devices is sucking up more than its fair share of power. The company is four years old but raised a series A round of $3 million from Felicis Ventures and Acorn Ventures last summer.

10). WegoWise: WegoWise is looking to lower energy costs for apartment buildings, helping both landlords and tenants. The company uses lots of data to help property managers see where their units can stand to be improved. WegoWise bought data startup Melon Power late last year.

11). Retroficiency: Retroficiency has created data analytics that basically can give a building (or a group of buildings) an energy audit remotely, without auditors having to come to the site of the building. It uses a lot of publicly and privately available data to do that. The method is a much more low cost and quicker way to plan energy building reductions.

12). GridNavigator: GridNavigator’s software and cloud-based service perform energy consumption forecasts throughout the day to help building managers manage their power consumption. The company was founded in 2009 and is based in Redmond, Wash.

13). Honest Buildings: Honest Buildings doesn’t just collect energy data, but it has created a repository for building-related data enabling renter and home buyers, property managers, and organizations to learn about and compare the energy efficiencies of buildings. It also has info about green building materials and certifications like LEED.

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Empower consumers

The most direct way to do this is to go straight to consumers and let them monitor their power usage so they can change their behavior accordingly. This is where companies such as Wattvision and PlotWatt come into play by connecting to users’ smart meters and displaying energy usage, warnings on thew web and mobile apps. It’s simple information, simply delivered.

Empower utilities to empower consumers

On the other hand, some startups are taking a more-removed approach to reaching consumers by partnering with utility companies, device manufacturers and others to offer a deeper service than an app can provide. Opower, for example, uses big data technologies to let utilities provide advanced analysis of power usage to their users. Companies such as EcoFactor, which announced $8 million in new funding on Thursday, lets utilities offer smart thermostats that users can control over the web, but also uses energy data and weather data to automatically adjust the temperature for maximum efficiency.

Tendril is among the kingpins of this space. It has a slew of utility and appliance partners, as well as a cloud platform on which developers can build applications that leverage its vast collection of energy data. Underpinning all of this is some serious data analysis that, like what Opower and EcoFactor do, learns and recommends based on users’ behavior.

Just make buildings more efficient

Somewhere in the middle of the power-to-consumer and utility-partner approaches lies WegoWise. It’s trying to lower energy costs in multi-family units such as apartment buildings in order to save both landlords and tenants lots of money. It’s also not relying heavily on complex algorithms — just lots and lots of data to help property managers see clearly where their units can stand to be improved.

According to WegoWise Founder and CTO Barun Singh, his company analyzes utility data for about 10,000 multi-family units and collects data from about 500,000 utility bills. Its customers aren’t the types that can justify equipping their properties with lots of sensors and real-time information systems, but they do need some sense of how their buildings are performing energy-wise. So, he explained, WegoWise will let customers compare usage across their own property portfolios, as well as against other similar buildings.

Singh said he thinks services like WegoWise will help ensure more buildings get retrofitted because property managers can identify upfront which ones might need the most work right away. Once they know this information, they can schedule an energy audit and have an expert identify the steps necessary to improve efficiency. The alternative, he said, is for someone to get audits on all their buildings — an expensive proposition they might rather avoid altogether.

“Our goal is not to replace the auditor,” Singh said. “Our goal is to ensure more audits are done.” Already, he added, WegoWise is working with an affordable-housing organization in the Boston area and has identified “huge savings” that landlords could make to save their residents money on their power bills.

On top of their utility bills, WegoWise asks customers for about 30 additional data points — “enough [data] that we can actually do something useful with it,” Singh said. Factors such as year built, living area, type of building, materials and other things can provide valuable insights about how much energy certain units should be consuming assuming normal usage by tenants.

But the key to making WegoWise work — just like consumer products such as Nest, EcoFactor and PlotWatt — is making it a joy to use, Singh said. It has to use data and infrastructure everyone already has, so as to not be too cumbersome. But in aggregate, that ends up generating a lot of information. “It turns out if you have a whole lot of that data,” Singh added, “you can actually do some interesting things.”

Feature image courtesy of Shutterstock user Kovalchuk Oleksandr.

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