SolarPrint pioneers next wave of indoor energy harvesting

For the past three years in Dublin SolarPrint has been quietly developing its solar cell technology, which has the potential to transform the wireless sensor industry, and help buildings, especially homes, become smarter and leaner in terms of their energy usage.

The company is now ready to share its technology with the world. Next week, SolarPrint will be presenting at ID Tech Ex in Boston, sharing the podium with speakers from companies such as Philips, Analog Devices, Ford Motor Company, Sharp, InStep NanoPower, Volvo Technology; US entities such as the National Institute of Aerospace, the Naval Research Laboratory; plus representatives from MIT, Princeton, University of Iowa, and Imperial College London.

A few weeks ago I had a unique opportunity to visit SolarPrint’s facility out in Sandyford Industrial Estate, a hub in Dublin for tech companies, with industry giants such as Microsoft based there.

Roy Horgan, one of SolarPrint’s founders, gave me a tour of the facility. Via a glass partition, I was able to see the scientists hard at work in both the lab itself and the cleanroom, with each of the solar cells produced at the company’s HQ inspected at minute level before they are deemed ready.

The company was set up in 2008 by Horgan, Dr Mazhar Bari and Andre Fernon.

SolarPrint has pioneered a new type of solar cell technology that actually converts light from any source of energy, even the ambient lighting in your home.

Used in wireless networks, the company’s technology could signal a powerful new means of helping to create smarter buildings of the future, and might even help to prolong batter life in mobile phones down the line. But more on that later.

Right now 40pc of the world’s energy is consumed by buildings of which 70pc of this is lighting and heating.

_{SolarPrint scientist at work in Sandyford}

Working with dye-sensitised solar cells (DSSC), SolarPrint’s low light solar cell technology enables the powering of wireless sensors/batteries, which in turn enables higher power and more functional sensors, explained Horgan.

“It increases the life of the battery so they don’t need to be maintained and changed. We’re making all these sensors self-powered.”

The problem, up to now, with wireless sensors has been the batteries, he said.

Think of the simple Casio calculator we all used in our school years, powered by light. Well SolarPrint’s technology works along the same principle, with its solar cells harvesting indoor light.

In such a short space of time, SolarPrint has fine-tuned its solar technology to power wireless sensors for buildings, and manage them. The next step is engaging with companies. While SolarPrint already has four Letters of Intents and MOUs, Horgan said that that over 70 companies from around the globe have been showing interest in its technology.

“Over 25 companies are looking for us to ship products to them and they are some of the biggest household names in this whole space,” explained Horgan.

He said big players like Siemens, Honeywell and Schneider would all be SolarPrint targets.

“What we’re doing is working with sensor companies to develop fully integrated solutions for companies such as Siemens. We’re also working with some incredible senor-based companies such as Gas Sensing Solutions in Scotland, Analog Devices and the EnOcean Alliance in Germany.”

DSSC technology was first invented by Michael Grätzel and Brian O’Regan at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland in 1991. Otherwise known as Grätzel cells, DSSCs are electrochemical devices comprising a light-absorbing molecule anchored onto semiconducting titanium dioxide (TiO2) nanoparticles, which make use of sunlight to generate electricity, said the SolarPrint team.

_{SolarPrint solar cell tech in action}

SolarPrint is now at the stage where it has an application, which is performing very well, ie wireless sensors.

Horgan believes that the wireless sensors markets is about to explode, especially with issues such as energy security now taking centre stage, as utilities try to keep up with new technologies and the evolution of smart grids.

Creating smarter buildings of the future

Horgan said the first step for SolarPrint would be the wireless sensor marketplace.

“I see the first stage as wireless sensors. I then see outdoor sensors, consumer electronics such as wireless keyboards. Within three to five years I also see this technology being deployed onto mobile phones.”

But, can mobile phones self-harvest their own energy to charge themselves?

“You actually can,” said Horgan. “Take the back lights via the LED. We only see 8pc of our power via the lights. If you had a conductor, a transparent layer behind it, you actually could power a phone by the battery itself to prolong battery life. I don’t think solar cells will ever power up mobile phones, as you would need to many of them, but because many people are gaming now and taking photos via their phone, you would need something there to prolong the life of a battery.”

ROI in less than two years

Horgan said that by rolling out a building energy management sensors network as part of a building energy management system the building’s owner or manager can monitor and control lighting and heating. “In turn, this will in turn will reduce the cost of one’s energy bills by as much as 40pc.”

The US recently passed a bi-partisan bill called the SAVE Act, which means people who are now getting a mortgage will be entitled to about US$2,000 on top of their mortgage to invest in energy efficiencies.

The main benefit of turning to wireless networks, according to Horgan, is that as opposed to wired solutions, wireless sensors will reduce the installation costs of this sensor network by as much as 40pc.

“It can roll out 10 times faster as there are no wires, thus giving the customer a payback on their investment in less than two years.
In addition, with many buildings having to be retrofitted to comply with building regulation standards, Horgan says the advantage of wireless networks is you don’t need to tear down walls to change wiring, etc. Instead, wireless sensors can be installed in less than two days.

So wireless sensors using solar cells appear to a win-win, both in terms of preserving architecturally rich buildings and in terms of giving you a fast return on investment. SolarPrint appears to be definitely one to watch in the next few years.

_{Eventual applications for wireless sensor networks to help create smart buildings of the future, as SolarPrint sees it}