Georgia Apostolou

Modelling the Performance of Product Integrated Photovoltaic (PIPV) Cells Indoors

In this paper we present a model, which have been developed for the estimation of the PV products’ cells’ performance in an indoor environment. The model computes the efficiency and power production of PV technologies, as a function of distance from natural and artificial light sources. It intents to support designers during the energy stability calculations, while creating PV-integrated products for indoor use. For the model’s validation, we tested indoors the PV cells of 10 commercially available PV-powered products in the power range of 0.8mWp to 4mWp, under three types of artificial illumination (halogen, fluorescent, LED lights) and natural light. Due to the model’s purpose to support the design process, its accuracy is not required to be high. Besides, given the difficulty to precisely measure low irradiance (< 20 W/m²) up to this point, it is unmanageable to succeed precise results. The measurements’ analysis revealed that the model could sufficiently predict PV products’ cells’ performance under CFL, LED illumination and mixed indoor light with a typical error around 25%. Measurements showed that under typical mixed indoor irradiance of up to 20 W/m², a-Si cells’ efficiency ranges between 5-6%, c-Si cells’ between 5- 7% and mc-Si cells’ between 4-6%.

Product-Integrated Photovoltaics

Product‐integrated photovoltaics (PIPV) is a relatively new field of interest in the PV community with great potential to use photovoltaics in the direct context of energy consumption by products. This chapter illustrates each application area of PIPV based on established product categories of PIPV as indicated: consumer products; lighting products; business‐to‐business applications; recreational products; vehicles and transportation; and arts. A dominant factor in the design of PIPV is the required area on products surfaces that can be covered by solar cells. The typical area of solar cells in PIPV is determined by a trade‐off of the internal power consumption of a product, its characteristic run time that results from the user behavior, the available area on the product, the PV technology applied, the storage capacity, and the irradiance conditions in the products surrounding. In the near future one may find new PIPV applications in lighting products, boats and other vehicles, and in indoor sensor networks.