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Tesla’s solar roof rollout was ... meh. These other new solar power gadgets are cooler.

Tesla solar roof
Solar roof, battery, and vehicle, courtesy of Tesla.

Last Friday evening, Tesla founder and CEO Elon Musk unveiled three new products. The rollout — scheduled, oddly, for 8:30 pm Eastern — had been hyped for weeks, but the actual event turned out to be a bit [sad trombone]. It was a fairly transparent bid to justify the proposed merger of Tesla and SolarCity to investors, but if I were one of those investors, I would not be very reassured.

Still, the market Tesla is targeting — which doesn’t yet have a snappy name but involves consumer-side electricity generation, storage, and management, along with electric vehicles — is beginning to hop anyway. (I’ll cover a couple of the potentially groundbreaking new products in that market below.) Whether or not the Tesla/SolarCity merger succeeds, that market is destined for big things.

First, though, let’s get the Tesla news out of the way.

Tesla has developed a solar roof, but we still don’t know much about it

The biggest news was the long-rumored solar roof. Specifically, Tesla has developed four different styles of rooftop solar shingles: Tuscan, slate, textured, and smooth.

tesla rooftop solar tiles (Tesla)

From a purely aesthetic perspective, these are pretty slick. They are made to appear almost indistinguishable from normal shingles from a low angle (i.e., when viewed from the street), while the view from above reveals embedded solar cells.

According to Musk, these roofs can be expected to last much longer than a normal roof — up to 50 years, versus around 20 — because the shingles are much more resilient than typical roofing shingles; they are covered with a layer of tempered glass. This is what happens when you drop a weight on them:

roofs under pressure
The best roof to fend off a small meteor.

And ... that’s about all we know about them. Musk had nothing to say about how much energy they would generate, how much they would cost, who would sell or install or repair them, how they could be prevented from overheating in intense sunlight, or when they would be available. (Julian Spector has a good take on the many unanswered questions.)

The whole thing was less like a product introduction than a trailer for a product introduction, which seems like a strange move for a company already facing investor skepticism. There was nothing in this announcement to reassure investors that Tesla has a solid business plan for solar roofs. It showed that Tesla can make a pretty product, but then, everyone already knew that.

There was also the Powerwall 2, the new version of Tesla’s home battery. It is basically a bigger, boxier version of the first Powerwall, with twice the energy capacity. (Musk claims it can power a four-bedroom house for a full day.) Importantly, it also has a built-in inverter, reducing the need for additional equipment and installation work.

tesla powerwall 2
The Powerwall 2.0, on a wall.

Along with the Powerwall 2 was the Powerpack 2, which began shipping in September. The updated version of Tesla’s utility-scale battery storage packs twice the energy density and the "lowest cost, highest efficiency and highest power density utility-scale inverter on the market." The first couple of Powerpack 2 installations are already underway.

Tesla Powerpack 2
Tesla Powerpack 2.

All in all, it was an underwhelming show from Tesla. The roof tiles are handsome, but all the details relevant to their commercial prospects remain unknown. The batteries are getting better and the Gigafactory is paying off, but we already knew that too.

So, all right, forget Tesla. They’re not the only ones who make cool things! There are many, many other companies developing products for this nascent market. Let’s look at a couple of cool energy gadgets that have debuted recently.

Meet the first solar panels with integrated storage and smart software

In September, a company called SunCulture released the SolPad and SolPad Mobile, which are, for my money, the coolest energy tech to debut this year.

The SolPad is a rooftop solar panel, a battery, an inverter, and energy management software all in a single unibody enclosure.

SolPad Home
SolPad for roofs.

The battery on the back side is not a standard lithium-ion, like Tesla’s, with a liquid electrolyte. Instead it is solid-state, which the company claims is less flammable, has a wider range of operating temperatures, and lasts much longer than standard lithium-ion batteries.

The panels snap together like Legos, with a little widget called the Connect:

SolPad Connect
SolPad Connect.

The last panel in the string is connected to any normal home electrical outlet — no fancy custom wiring required.

A few nifty features:

  • The "Flexgrid" inverter is smart, i.e., if it senses a failure in the grid (a blackout), it will switch over and provide power directly to the home. This allows the home to "island" itself into a self-sufficient microgrid (at least for a while).
  • Each panel can send power to the home, the grid, or its internal battery, depending on conditions set by the homeowner.
  • Each panel battery can store .5 kWh, though there's an optional upgrade to 1 kWh. A 5.3 kW SolPad system comes with about 12.5 kWh of storage. (The current Tesla Powerwall holds 7 kWh; the Powerwall 2 holds 14 kWh.)*
  • The software running all this is called SolControl, which the user can control through an app that "gamifies" (barf) energy savings.
  • You can put a little widget called the SolControl plug between any electrical device and its wall outlet (there’s also a SolControl Breaker for larger appliances like water heaters), and it becomes part of the smart home energy system, controllable through the app. Each SolControl plug communicates usage data to the panels wirelessly.
SolControl plug
SolControl plug.
  • The SolControl app shows users how much energy each panel is generating and how much each has stored in its battery, along with how much power every device in the home is consuming. Users can direct energy from individual panels to individual devices, appliances, or rooms. You can control all your home devices remotely, from anywhere, with the app, which will remind you if you’ve left something on while you’re away.
SolPad app
The SolPad app

Pretty impressive stuff.

The company projects that total installed costs of SolPad rooftop systems will be up to 50 percent less than comparable systems. (Of course, comparable systems would include solar panels, storage, and control software, which is a pretty high-end package.) They say they’ll achieve these cost reductions through "the integration or elimination of balance-of-system parts," reductions in "soft costs" like customer acquisition and installation, and manufacturing efficiencies.

There’s one more cool part to this: the SolPad Mobile. It is, as the name indicates, a freestanding, portable version of the SolPad.

SolPad Mobile
SolPad Mobile.

It’s small enough that a single person can easily carry it. On the back, it’s pretty simple. There’s a port to connect it to a normal electrical outlet (at which point it will feed energy into the building). There’s a port to connect it to another SolPad. And there are a few USB ports, for phone charging and the like.

SolPad Mobile, back
SolPad Mobile, back ports.

Any number of these can be easily connected to one another to form an impromptu microgrid.

SolPad microgrid
SolPad microgrid.

Fun extra: SolPad Mobile talks to you. There’s smart software inside and the surface is pressure-sensitive, so you can just tap it and it will tell you how best to orient it to maximize power generation, how much it’s generating, and how much juice is left in its battery.

All the promotional materials show well-groomed white people using the SolPad Mobile on their fancy decks, but the obvious applications for this kind of product are in the developing world, many parts of which lack reliable electricity.

Remote communities with no grid connection could use this system as a sturdy, scalable, and dead-simple source of power, to charge their phones or run electric lights. Urban households connected to an unreliable grid could use it for backup power, ensuring that their most important devices or appliances remain running even as grid power goes in and out.

Remote research, military ground operations, field hospitals in areas struck by disasters — the uses for portable power and storage like this are endless.

SunCulture is making a huge bet here: that integration and ease of use will do for solar what they did for PCs, i.e., justify higher upfront costs. If you want to know more, watch this overwrought but informative video:

More cool energy stuff: power-generating windows

Okay, I got really excited about the SolPad, so I’ll be more brief on this one.

In July, a new company called Solar Window Technologies, which has been working in collaboration with NREL, unveiled its SolarWindow. It is, as the name suggests, a window that generates power. Here’s how the press released describes it:

The company’s SolarWindow™ generates electricity when its transparent organic coatings are applied in thin layers on to glass surfaces. The SolarWindow™ Intra-Connection System, announced today, moves electricity within these electricity-generating coatings to the company’s previously developed ‘invisible wires’. In turn, these ‘invisible wires’ transport electricity across the surface to the edge of the glass, where it’s connected to building electrical systems.

The "invisible wires" are "approximately 50 micrometers (µm) wide," which is effectively invisible to the naked human eye.

The result is a normal-looking window with a pleasant tint.

solar window
(Solar Window Technologies)

The company says the windows, unlike conventional or crystalline PV panels, work in "natural, shaded, and even indoor light." The target application is large urban towers and skyscrapers, where SolarWindow can outperform conventional PV "50-fold," the company claims — for the simple reason that conventional PV only fits on a tiny area on the roof, where solar windows can cover the building and capture all light, from any angle.

The company claims a one-year payback, based on "independently validated financial modeling results." In part, those savings are due to the way the windows are manufactured. The process requires no high-temperature or high-vacuum production techniques (unlike most thin-film solar products). Applying thin layers of liquid to glass is well-suited to "high-speed manufacturing techniques" like "roll-to-roll and sheet-to-sheet manufacturing."

And there are big opportunities in the big-building market. Commercial buildings use about 40 percent of US electricity. A full solar window installation can cover 30 to 50 percent of a skyscraper’s energy consumption needs.

Crucially, the company has also developed a transparent veneer that can be applied to existing windows, which opens up an enormous retrofit market. Making existing buildings into solar generators doesn’t require any new land or space — and there are more windows than there are rooftops.

The integrated electricity market is coming, Tesla or no Tesla

The point of all this is that the market Tesla is targeting with its acquisition of SolarCity (I really need a snappy name for it) is going to flourish whether or not Tesla’s particular products succeed.

I have no idea if the SolPad or SolarWindow will be commercially successful. But if SolPad is not the user-friendly all-in-one solar product that busts out into the mass market, some other version will be. Now that researchers know how to make windows into power generators with liquid polymer coatings, some company is going to figure out how to capture that market, whether or not it’s SolarWindow.

It will sputter and lurch for a while, with lots of startup casualties, but this market is going to happen. Solar is getting cheap and super, super small; as that happens, it will be integrated into more and more products, from roofs to windows to roads to parking garages to fabrics to tents and backpacks. Similarly, batteries are getting cheaper and more sophisticated and will be showing up in more and more places.

Eventually, power generation and storage will become ambient, something that simply happens, throughout the urban infrastructure. With that will come more and more sophisticated software for managing, sharing, and economizing all that power. (Al Gore used to call this coming electricity-internet hybrid the "enernet," but it never really took off.)

In this arena, as in others it has entered, Tesla’s main goal is to accelerate the market’s maturation — to push forward a sustainable future. Its rooftop solar tiles will likely end up a footnote in the grand scheme of things, but the market those tiles are attempting to jump-start will one day change the world as much as the internet has.

* Correction: Originally the post said that each individual SolPad has a battery that can hold 12.5 kWh. That is obviously bonkers. In fact, the 12.5 kWh figure is for a 5.3kW SolPad system, composed of panels that individually store .5 kWh.

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