New Parallel Solar Technology from eIQ Energy

We spoke with Oliver Janssen and Michael Lamb at eIQ Energy to find out more about their technology and products.

Transcript

DB: This is David Belden with Residential Solar 101 and I’m here with Oliver Janssen, the CEO of eIQ Energy and Michael Lam, the VP of Business Development of eIQ Energy.  Thanks for joining me.

OJ: Thanks David

ML: Thanks for having us.

DB: Michael, could you give us an overview of the technology.

ML: Sure, so to date, the way the industry has gone is that they needed to be able to take the voltage off of your solar modules and get it to a level that is sufficient for the inverter to be able to convert that energy from the DC source of solar to AC which is what we use in our homes.  Unfortunately in order to do that you needed to string a number of panels together in series. This is very similar to the Christmas tree light effect that you get.  When you have a bulb that goes out with your Christmas tree lights, and all of the other pages go out with it.  The same kind of effect happens with your solar system.  So we’ve come out with a technology that helps you connect your systems in parallel.  And by connecting them in parallel you avoid that effect. So now each individual module is free to deliver its maximum power to the inverter at all times.  And what this does is it greatly enhances the performance of over all system through all sorts of environment conditions, such as shade and work dirt. 

DB: So does that mean that people who were previously not a good fit for solar due to shading, roof angle and whatever else may now be a better candidate using your technology.

ML: With out technology, because of its parallel nature, you’re able to put modules on every face of your home.  As long as it’s seeing sun for some part of the day, you can still have a module on that part.  The other advantage is that you can do all of that into the same inverter, and that’s a huge cost savings. 

DB: We’ve heard a lot about microinverters as a new technology that allows systems to last longer and/or one that’s becoming appealing to home-owners. Is this similar to using micro inverters or does it have similar outcome?

ML: It’s similar in the sense that microinverters are also a parallel technology. The difference is that each little microinverter, by its name is converting the power from the module into AC. Our solution allows you to maintain the DC essence of the power coming off of the modules.  And deliver that back to a central point of inversion.

OJ: Maybe I can add to that.  I think there are some important similarities and some important differences.  The key similarity whether you’re using a microinverter or a DC Boost technology like eIQ’s, you have a parallel system and you’ve eliminated the strings of panels. The difference is with a microinverter the DC to AC conversion occurs at each panel.  Whereas with our parallel solar architecture we’re preserving the central inverter and we think that ultimately that provides for a more reliable system because you’re dealing with one inverter that is always seeing an optimal input of voltage.  And so we believe over time we’ll be able to demonstrate an improvement in inverter performance and reliability. 

OJ: Our system is comprised of several components. The first is the DC Boost using which we call the V-Boost, which attaches to the panel.  The second is the V-Com unit, which stands for communication unit) which pulls the data off of the power line and reports the performance of the system on a per panel basis back to the residential home owners computer system.

DB: And what sort of improvements would someone see over the life of a 5kW system?

OJ: I think there are several categories of improvements.  The first thing we would see is an improvement, a reduction really, in the design time and the installation time required for the system because you no longer have to design against or around roof obstructions or difference types of panels, shading, soiling.  Essentially you can tile your roof and the DC bus will connect all of the panels back to the central inverter.   So I think a reduction in upfront cost is one of our key value propositions.  A second is that there’s a potential for incremental power harvest because we are controlling and optimizing the performance of the system at the panel level instead of at the inverter level so that each panel is optimized.  Regardless of its unique operating conditions – whether for example it’s got some bird droppings on it, or it’s in the shade, or it’s on a different roof orientation. That panel will operate at its optimal combination of voltage and current without affecting the performance of its neighbors. So we would expect to see 5 to 25% improvement in energy harvest over time.

DB: That’s impressive.

DB: So it sounds like if you’re not using parallel boost technology, if one of the panels is dirty or slightly shaded then it brings down the performance of all of the other panels.  And this allows each panel to work at its optimum…

OJ: Right.  That’s exactly right.  In conventional series architecture if an individual panel becomes compromised in any way, whether it becomes shaded or dirty, it will affect the performance of its neighbors.  Because it will effect the voltage of the string. 

DB: You had mentioned that there was a piece of the system that communicated with a home computer or Internet. What sort of data will a homeowner be able to get?  From what I hear, looking at how much power you’re saving, or that your system is producing, is half the fun.

OJ:  Yeah, so it is exciting.  You know you can see the system come up in the morning and track performance during the day.  And even if you were to see a cloud move across the roof you could see your power drop momentarily then come back up as the sun came out.  Essentially we report on the panel voltage and current going into our V-Boost unit then on the output current and voltage coming out of our V-Boost unit and onto the DC Bus.  We also report on the temperature of the V-Boost unit, which is a proxy for the temperature of the panel.  And finally, we have some very important safety features.  Our communications system is able to remotely turn the units on and off.  So for example, if you were going to do some maintenance on your roof and you wanted to be sure there was no voltage present – no high voltage DC present – you would turn off your inverter and automatically you would know that there was no voltage on the array. 

DB: That’s critical.  Because otherwise you can get a lot of voltage off of these.

OJ: Or, in an emergency situation where you might have a fire for example.  This is currently a big safety issue with a series architecture, where there is no way to turn off the voltage unless you can cover the panels.

DB: So with all that information a homeowner would then be able to tell if they actually need to clean their panels, or more likely, don’t need to clean them.

OJ: Absolutely.  If you saw a drop in performance you could trouble shoot that very quickly.  You could pin it down to the individual module.  You might have a tree branch that’s fallen on your module or some other obstruction that’s occurred and in real time you’d be able to tell. 

DB: Will your power-boost therefore work with any panels out there?   

ML:  Exactly.  It works with thin film.  It works with crystalline.  In fact, in one of our early on installations we actually have 3 different technologies feeding the same inverter, which before our technology was unheard of.   We have amorphous silicon, we have crystalline, and we have cad-tel all feeding into the same inverter.

DB:  So in theory you could grow a system over time – if as you add additional panels as your energy use increased by either growing your business or growing the size of your family?

ML: Exactly.  Exactly.

OJ: As an interesting aside, one of the advantages obviously is the mixing and matching of panels that Michael is describing.  But our DC Bus can take any power source. You could put a wind turbine on this system or a fuel cell. And really you can think of it as a DC power backbone for your home.  So if you had a home owner that was interested in other types of renewable energy – whether it’s a wind turbine or a fuel cell or even a battery all of that could be connected to the parallel solar DC bus.

DB: Now if a home-owner or anyone watching this wants to use it in their future home solar installation, how can they learn more?

OJ: I think the best thing to do is to visit our website, www.eiqenergy.com.  There is a lot of background information about the product.  But also there’s importantly a list of our distributors that carry the product who are also very knowledgeable.  One in particular, DC Power is a well-known distributor here in Northern California. But we also have distribution partners for any part of the country.  So I’d start with he website.

DB: Any other thoughts to add before we wrap up?

OJ: I appreciate the opportunity to tell your audience about our technology and products.

DB: Thank you very much for joining me. This has been a pleasure chatting with Oliver and Michael from eIQ Energy and we look forward to bringing you more solar technology in the future. 

by Matthew Ryder-Smith