**9. Environmental impacts**

Throughout the life cycle, the PV industry can generate potentially toxic compounds, either during normal production or during accidental situations that could be released into the atmosphere, in solid or liquid effluents. The possible consequences would include alterations in the quality of the air, the soil and the water, with potential impacts on biota (Electric Power Research Institute, 2003; SVTC, 2009).

Photovoltaic Conversion: Outlook at the Crossroads

indicate that more in-depth investigation is required.

Villoz, 2009).

developments.

**10. Sustainable development: Issues and prospects** 

Between Technological Challenges and Eco-Strategic Issues 329

2009) and there is a possible bioamplification of CdSe nanoparticles (Werlin et al., 2011). Overall, there is a consensus that the evaluations performed to date seem to give the PV industry much more credit than fossil fuels, but the fragmentary nature of the results

The current vitality of the photovoltaic sector is taking place in a context marked by the need to review energy policies given both the increasing spectre and the growing number of the obvious consequences of climate change. In fact, the current policies serve only to draw sombre and unfavourable prognoses, resulting in particular from a lack of balance between a high rate of energy consumption and a problematic supply of conventional fossil energies associated with highly volatile prices and market instability (Bradford, 2006; Labouret &

The current concept of sustainable development is positioned as an enlightened response to major concerns, based on the fact that it reconciles, inasmuch as possible, three parameters which have been completely divergent to date: the economic efficiency, the social equity and the socio-economic development and, finally, the preservation of the ecosystems. The compromises sought through sustainable development require the implementation of several complex actions focussed on a fundamental objective: to ensure a balance between the energy offer and demand for current generations while respecting the resilience of the biosphere. It is, therefore, a response to real, current concerns that could compromise the wellbeing of future generations (International Union for Conservation of Nature, 2006). Applied to the energy sector, such actions involve the implementation of strategies that are essentially corrective in nature and are part of a dynamic process based on the guiding principal of using renewable natural resources. Given this more functional vision and, based on the economic, health, safety and environmental profiles of PVs, as assessed and presented throughout the chapter, it is possible to provide an overall appreciation of the extent to which the photovoltaic industry respects different principles of sustainable development, inspired by those defined by the Ministry of the Environment of the Province of Québec, Canada (MDDEP, n.d.). This assessment is based on the current state of knowledge for an industrial sector extremely fertile in terms of technical and technological

Table 4 aligns the PV industry with several principles of sustainable development. It can be considered as a barometer of human and equitable sustainable development. It also summarizes the extent to which different principles of sustainable development are respected. Although the results may be considered favourable, recommendations are issued

Despite the universality of the sun as a resource and the fact that it is inexhaustible and safe, there are still many issues. Whether they are technical or technological, they will require a solid political focussing on subsidy systems and financial accessibility, strong programs to integrate photovoltaic systems in buildings, and administrative flexibility to ensure that the

Moreover, a major issue concerns the social acceptability of PV systems, not only as a source of reliable energy but also as a system that can easily accompany daily life at a reasonable

cost, while being integrated into local architecture without major visual impacts.

in order to enhance the respect for the various principles.

sector is dynamic (Bradford, 2006; EPIA/Greenpeace, 2011).

The vast majority of the studies on ecotoxicity and potential environmental impacts essentially pertain to the plant manufacturing phases, whereas little data is available with respect to the possible direct emissions or releases during operation as well as during the dismantling, the processing of waste and the recycling of the solar panels.

In terms of atmospheric emissions, the principal pollutants are essentially sulphur oxides (SOx), nitrogen oxides (NOx) and certain heavy metals such as arsenic, cadmium or mercury (Fthenakis, 2009; SVTC, 2009). Table 3 compares the average SOx and NOx atmospheric emissions from PV systems to those from various fossil fuels used to produce electricity. The results provide eloquent evidence that PV systems are clearly advantageous comparing to various fossil fuels. The data concerning PV systems varies according to the technologies used, the energy performances of the solar cells, the capacities of the systems, the impact assessment methods used and, therefore, the databases used.


Table 3. Average SOx and NOx atmospheric emissions associated with energy systems

The PV industry also produces ammonia emissions (NH3) and volatile organic compounds (VOCs) (Pehnt, 2006; Fthenakis et al., 2010), but the existing data cannot be used to provide a rigorous comparative assessment. If there is a stage that could be crucial for the PV industry, it would be the end of the systems' lifecycle. Indeed, this could be the source of environmental and ecotoxicity concerns. In fact, the potentially toxic materials involved throughout the life cycle could be found, as a result of a routine or accidental release, in the solid and/or liquid effluents that could contaminate the soil and aquatic environments (Electric Power Research Institute, 2003; SVTC, 2009).

The emerging technologies require just as much vigilance as a result of the shortage of current ecotoxicological data, which would invite more refined investigations in the future in order to keep up with the growing dynamics of the market. The cadmium-based PV industry is specifically concerned since the current data seems to indicate that CdTe nanoparticles have the potential of bioaccumulation in aquatic organisms (Peyrot et al.,

The vast majority of the studies on ecotoxicity and potential environmental impacts essentially pertain to the plant manufacturing phases, whereas little data is available with respect to the possible direct emissions or releases during operation as well as during the

In terms of atmospheric emissions, the principal pollutants are essentially sulphur oxides (SOx), nitrogen oxides (NOx) and certain heavy metals such as arsenic, cadmium or mercury (Fthenakis, 2009; SVTC, 2009). Table 3 compares the average SOx and NOx atmospheric emissions from PV systems to those from various fossil fuels used to produce electricity. The results provide eloquent evidence that PV systems are clearly advantageous comparing to various fossil fuels. The data concerning PV systems varies according to the technologies used, the energy performances of the solar cells, the capacities of the systems, the impact assessment methods used and, therefore, the

(g/kWh) References

Hatice & Theis, 2011.

Theis, 2011.

Theis, 2011.

2011.

Gagnon et al, 2002; Fthenakis et al., 2008; Jaramillo et al., 2007; Hatice &

dismantling, the processing of waste and the recycling of the solar panels.

NOx

Photovoltaic 0.05 to 0.36 0.025 to 0.34 Pehnt, 2006; Fthenakis et al., 2008;

Heavy fuel 1.1 to 8.0 0.5 to 1.5 Gagnon et al., 2002; Hatice & Theis,

Diesel generator 0.2 to 1.3 0.3 to 12 Gagnon et al., 2010; Hatice and

Table 3. Average SOx and NOx atmospheric emissions associated with energy systems

The PV industry also produces ammonia emissions (NH3) and volatile organic compounds (VOCs) (Pehnt, 2006; Fthenakis et al., 2010), but the existing data cannot be used to provide a rigorous comparative assessment. If there is a stage that could be crucial for the PV industry, it would be the end of the systems' lifecycle. Indeed, this could be the source of environmental and ecotoxicity concerns. In fact, the potentially toxic materials involved throughout the life cycle could be found, as a result of a routine or accidental release, in the solid and/or liquid effluents that could contaminate the soil and aquatic environments

The emerging technologies require just as much vigilance as a result of the shortage of current ecotoxicological data, which would invite more refined investigations in the future in order to keep up with the growing dynamics of the market. The cadmium-based PV industry is specifically concerned since the current data seems to indicate that CdTe nanoparticles have the potential of bioaccumulation in aquatic organisms (Peyrot et al.,

natural gas 0.14 to 1.8 0.3 to 4.5 Jaramillo et al., 2007

databases used.

Liquid or solid

Energy system SOx

(g/kWh)

Coal 5.2 to 12.0 1.3 to 4.5

(Electric Power Research Institute, 2003; SVTC, 2009).

2009) and there is a possible bioamplification of CdSe nanoparticles (Werlin et al., 2011). Overall, there is a consensus that the evaluations performed to date seem to give the PV industry much more credit than fossil fuels, but the fragmentary nature of the results indicate that more in-depth investigation is required.
