# Overview and Perspectives for Vehicle-Integrated Photovoltaics
## 2 Results and Discussions
#### 2.1.1 Overall View of the Market Offers and R&D Demonstrators  
Commercially available offerings and R&D demonstrators of embedded photovoltaics are found on a variety of vehicle types such as private cars, camper vans, trains, trucks, passenger ships, planes, or spatial vehicles. Some examples of these vehicles (proof-of-concept, prototype, or commercial vehicles) [5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15; 16; 17] are shown in Figure 1.  
Figure 1: \(Cont.\)A thorough list of VIPV commercial offerings and R&D projects is shown in Table 1, including information such as module efficiency, cell technology, PV surface or power, model, manufacturer, and use of the PV-generated electricity. \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Type** & **Manufacturer** & **Model/Project** & **Stage** & **Year** & **Vehicle** & **PV Surface** & **PV** & **Cell Technology** & **PV Use** & **References** \\  & & & & **Weight (t)** & **(m\({}^{2}\))** & **(w\({}_{\text{PP}}\))** & **(w\({}_{\text{PP}}\))** & **Cell Technology** & **PV Use** & **References** \\ \hline Ship & Eco Ship & & Development & 2020 & & 12,000 & 750 & & Aux. & [18] \\ \hline Ship & Planet Solar & Téranor & Proof of concept & 2010 & 89 & 516.0 & 93.5 & Silicon (Si) & Prop. + Aux. & [13] \\ \hline Ship & Energy Observer & Energy Observer & Proof of concept & 2017 & 28 & 130.0 & 21 & Silicon & Prop. + Aux. & [19] \\ \hline Ship & SoelCat & Catamaran 12 & Proof of concept & 2017 & 6 & & 8.6 & & Prop. + Aux. & [20] \\ \hline Bus & Fast Concept & Starter & Proof of concept & & & 20.5 & 3.4 & \begin{tabular}{c} Si mono \\ IBC/21.8\% \\ \end{tabular} & Aux. & [10] \\ \hline Camper & Detheffs & E-home & Proof of concept & 2017 & 5.6 & 31.0 & 3 & Silicon mono & Prop. + Aux. & [8,21] \\ \hline Car & Hyundai & Sonata Hybrid & Commercial & 2020 & & 1.3 & 0.204 & Si mono/22.8\% & Prop. + Aux. & [22,23] \\ \hline Car & Skoda & Superb & Commercial & 2000 & & & & Aux. & [24] \\ \hline Car & Gaia & Wiseman & Commercial & & 0.8 & & 0.23 & \begin{tabular}{c} Silicon mono \\ IBC \\ \end{tabular} & & [25] \\ \hline Car & Audi & A8, A6, A4 & Commercial & 1994 & & 0.04 & Aux. & [24] \\ \hline Car & Volkswagen & \begin{tabular}{c} Touang, \\ Phaeton, \\ Passat \\ \end{tabular} & Commercial & 1994 & & 0.04 & Aux. & [24] \\ \hline Car & Mercedes & \
\begin{tabular}{c} E class, \\ Maybach \\ \end{tabular} & Commercial & 1994 & & 0.04 & Aux. & [24] \\ \hline Car & Nissan &
\begin{tabular}{c} Leaf–SL \\ model \\ \end{tabular} & Commercial & 2014 & & Aux. & [26] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Noncomprehensive chart of VIPV products and R&D initiatives. Figure 1: (**a**) Proof of concept of the Lightyear One car [5]; (**b**) a car prototype—Sion from Sonomators [6]; (**c**) Detheffs motorhome demonstrator: E-home [8]; (**d**) a concept truck from Renault Truck—Optifuel Lab 2 [11]; (**e**) a set for freezer vehicles—TSSC S-Series [12]; (**f**) a ship proof of concept—Téranor form Planet Solar [13]; (**g**) a drone prototype from Atlantik Solar [14]; (**h**) a plane proof of concept—Solar Impulse [15]; (**i**) a spatial vehicle prototype: Stratobus [17]. \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
Among the projects listed in Table 1, the majority are car-based (Figure 2). They are mainly proof-of-concept or development vehicles with integrated PV; however, a substantial number of market offerings can be found for cars (Figure 2). According to the gathered data, the mean PV area for each kind of vehicle is significantly different (Figure 2). The mean embedded PV area ranges from 2.9 m\({}^{2}\) for cars to thousands of square meters for ships. Note that, although passenger cars have the lowest available surface, they have still become the leading application of VIPV. The higher number of passenger cars on the market may explain the higher interest in integrating photovoltaics into passenger cars. The limited surface area raises the demand for high module power density and exploitation of highly curved surfaces.