Page 54 - EE|Times Europe Magazine - December 2020

54 EE|Times EUROPE — Power Electronics

POWER ELECTRONICS
Advanced Solutions for Power Production

and Transfer

By Maurizio Di Paolo Emilio

pplications involving the production and transfer of energy cially if it can take place without requiring the use of bulky electrical
are of fundamental importance today. The search for cables. There is renewed interest in wireless electricity transfer
increasingly sustainable energy solutions, combined with the based on the principle of electromagnetic induction, thanks to two
A need to contain carbon dioxide emissions, favors the use of applications that have become priorities. The first is the charging of
renewable energy sources. battery-powered mobile consumer devices (typically smartphones),
The ability to produce energy from alternative sources such as which can be recharged simply by placing them on a suitable source
the sun, wind, wave motion, and biomass allows for a significant capable of transferring electricity by conduction. The second is the
reduction in environmental impact and polluting emissions compared recharging of batteries in electric and plug-in hybrid vehicles, carried
with traditional energy sources based on fossil fuels. Solar energy, out by means of devices that can be placed on the floor below the car
for example, can help developing countries and rural communi- or even integrated into the road surface. This solution not only dis-
ties to equip themselves with efficient, economical and virtually penses with electrical cables but is effective from a safety standpoint,
zero-environmental–impact plants for the production of electric- as it does not expose the user to the potential risk of contact with the
ity. Photovoltaic panels high power involved.
Below, we examine real applications relating to the exploitation
The search for have undergone a rapid of solar energy as a source of electricity and the transfer of wireless
and significant evolution
increasingly sustainable in recent years, offering energy in various contexts.
users increasingly efficient
energy solutions, and reliable solutions that FLEXIBLE SOLAR PV
combined with the require reduced maintenance Power Roll, based in Sunderland, U.K., has developed an innovative
and are able to produce
model of solar film capable of generating and storing energy. Light-
need to contain CO energy even in conditions of weight and flexible, the solar film can adapt to any type of surface,
2 low solar radiation. At the producing electricity at a cost up to 20× lower than traditional photo-
emissions, favors the same time, the introduction voltaic panels. The new technology is based on a flexible film patterned
use of renewable energy of flexible panels capable of with thousands of microgrooves. Each microgroove is a few microns
thick, smaller than a human hair.
adapting to various surfaces
sources. has made installation easier. The advantages of this solution include low cost (US$0.03/W for
Photovoltaic systems are the finished product), low weight (0.3 kg/m ), and high power den-
2
normally combined with sity (500 W/kg). Other benefits are easy installation and reduction of
special units for storing the electricity produced, made with storage maintenance times; sustainability, thanks to the use of fully recyclable
batteries that are more or less evolved according to the available materials and absence of rare earths; and adaptability. For example, the
budget. These batteries allow the accumulation of energy during the same techniques used on the roofs of buildings can be used for power-
day and then make it available for lighting and powering different ing small IoT sensors.
loads at night. They are also able to detect blackouts, automatically Figure 1 outlines the phases of the manufacturing process for flexi-
becoming the primary energy source in the event of a power failure. ble solar film. As shown in the figure, the flexible film enables
Unlike generators, storage batteries can deliver energy without the roll-to-roll manufacturing of capacitors using a range of dielectrics
use of fuel and can do so silently. and storage materials. This capacitor technology, employed for
Of equal importance to energy production is energy transfer, espe- storing energy, offers ultra-low-cost manufacturing; exceptional
energy density; multiple shapes and sizes,
with voltage and capacitance flexibility; and
enhanced operating lifetime compared with wet
electrolytic capacitors.
“Our technology has several advantages over
flexible solar technology,” said Neil Spann,
managing director at Power Roll. “It is extremely
easy to produce. There are fewer steps in the
manufacturing process. If you look at flexible
photovoltaics, we can say that it is much more
expensive. So, in reality, the main advantage of
our technology is cost-effectiveness.
“In terms of efficiency, our efficiency is good,
but we don’t aim to make the highest-perform-
ing solar panel in the world,” he added. “We
are looking for a compromise, a good level of
performance. So our current cell performance
is 11%, which is somewhat comparable to other
Figure 1: Steps involved in the manufacture of flexible solar PV film (Source: Power Roll) flexible solar panels like organic photovoltaics,

DECEMBER 2020 | www.eetimes.eu