Voltage measurement of each element and noting of the values in a logbook.
Check appearance: case normal, not distorted, clean terminals (if not clean them), no visible deposit at the bottom of the plates (which indicates a loss of actor material, visible when the case is transparent).
Check the connections: terminal clamps tight, cables in good condition, fuses in place and clean for all batteries.
Electrolyte level: plates well covered (top with distilled water if necessary), no deposit or suspect masses between the grids.
Measure the electrolyte density of each 2 V element: note the values in the same logbook as the voltages and compare the readings; if one or several readings are very different, carry out the measurements again after an equalisation charge and once more after several days in an intermediate charge state. If the densities remain very different, battery replacement should be considered if the capacity is no longer sufficient.
Check the voltage.
Check appearance: case normal, not distorted, clean terminals (if not clean them), the safety valves not distorted, no traces of electrolyte on the surface (which would indicate a high overcharge with loss of acid).
The checking of appliances is usually done regularly as they are used. However, fluorescent tubes age with time and the number of times they are switched on or off. When a DC fluorescent tube does not start easily, check that the wear of the electrodes (black halo) is the same at each end of the tube, otherwise turn the lamp in its socket (U-shaped tube) or reverse the ends (straight tube) and try again to start it. The black halo appearing at the ends comes from the degradation of the electrodes, which lose some matter at every cold start or if the wave is not symmetric (DC component). It is recommended to have spare fluorescent tubes that are often difficult to obtain in traditional sales outlets. If the ambient temperature is very low (in a chalet in winter, for example), wait until it has risen if the lamps cannot be started – it is also possible to take the tube out and heat it somewhere else (this can be done without problem up to 50 °C) if light is absolutely necessary in a cold room. If starting still proves impossible, do not keep trying, to avoid overheating the ballast, which, in general, has to dissipate more energy at start-up.
For the maintenance of low-energy bulbs operating on 230 V AC, there is no access to the tube, so when they do not start, they should be changed. However, the remarks above about low temperatures remain valid and it is also possible to heat the lamp before turning it on in the cold if it does not start immediately.
 PV contributes indirectly to the prevention of global overpopulation Insofar as there is generally a direct link between an increase in living standards and a reduction in the birth rate, PV technology contributes indirectly to the prevention of global overpopulation.
 PV generates economic activity and jobs
In countries where solar panels are produced, but also more or less everywhere where they are sold, installed and maintained, PV technology generates economic activity and additional jobs.
 W. Palz, J. Greif (eds.), European Solar Radiation Atlas: Solar Radiation on Horizontal and Inclined Surfaces, Springer-Verlag, Berlin; 2008.
 This is conventional in the PV field. The sign of the current is changed so that the current-voltage curves can be drawn above and not below the voltage axis, which is more convenient (Figure 2.27).
 Examples are the German cells manufactured by Q-cells and Ersol, the Japanese Kyocera cells, or the French Photowatt and Tenesol. For a directory of all manufacturers, see http://www. solarbuzz. com.
 P. J. Verlinden, R. M. Swanson, R. A. Crane, ‘High efficiency silicon point-contact solar cells for concentrator and high value one-sun applications’, Proceedings of the 12th EC Photo-voltaic Solar Energy Conference, Amsterdam, April 1994, pp. 1477-80.
 Sunpower Corporation.
 Kyocera Corporation. European PVSEC conference, Milan September 2007.
 The toughening of glass by chemical or thermal processes makes it much more resistant, and certainly virtually impervious to hail. As a consequence, it cannot be easily cut, and the toughening process is normally applied to ready cut sheets.
1000 V DC + twice the open circuit voltage of the system at STC for 1 min
For modules with a surface smaller than 0.1 m2, the minimum resistance is 400 MW. Larger modules are required to have the measured resistance times the area of the module greater than 40 MW/m2. Testing is performed using a test voltage of 500 V or maximum voltage of the system, whichever is higher According to details provided in 10.4 For further information, see IEC 60904-10
11 There is an independent standard on exposure to UV, IEC 61345, which stipulates the minimum doses of UVA and UVB the panels must be submitted to.
 K. W. Jansen, S. B. Kadam and J. F. Groelinger, ‘The advantages of amorphous silicon photovoltaic modules in grid-tied systems’, Photovoltaic Energy Conversion, Conference Record of the 2006 IEEE 4th World Conference, May 2006, vol. 2, pp. 2363-66.
S. Adhikari, S. Kumar and P. Siripuekpong, ‘Comparison of amorphous and single crystal silicon based residential grid connected PV systems: case of Thailand’, Technical Digest of the International PVSEC-14, Thailand, Bangkok, 2004.
 Photovoltaic and electronic thin-film laboratory, Institute of Microtechnology, University of Neuchatel, Switzerland.
 Interface and thin-film physics laboratory, Ecole polytechnique, Palaiseau, France.
 On these small cells and their experimental uses, see Cellules Solaires (details in Bibliography) and Figure 3.19.
 Even if the glass was originally toughened, the high temperatures that it undergoes when the thin films are deposited would destroy the toughening effect.
 See, for example, the work of the PHASE laboratory of CNRS Strasbourg.
 Sheffield Hallam University, results unconfirmed.
 C. R. Osterwald, T. J. McMohan, J. A. del Cueto, J. Adelstein, J. Pruett, ‘Accelerated stress testing of thin-film modules with SNO2:F transparent conductors’, Presented at the National Center for Photo – voltaics and Solar Program Review Meeting Denver, Colorado, 24-26 March 2003
 L. Torcheux, P. Laillier, ‘A new electrolyte formulation for low cost cycling lead acid batteries’, Journal of Power Sources, 2001;95:248-254.
 R. H. Newnham, W. G.A. Baldsing, ‘Benefits of partial-state-of-charge operation in remote-area power – supply systems’, Journal of Power Sources, 2002;107:273-279.
 M. Perrin, H. Doring, K. Ihmels, A. Weiss, E. Vogel and R. Wagner, ‘Extending cycles life of lead – acid batteries: a new separation system allows the application of pressure on the plate group’, Journal
of Power Sources, 2002;105:114-119.
 Directives generates pour l’utilisation des EnR dans l’Electrification Rurale Decentralisee (Directives ERD) (Juin 1997).
 The Cold Chain Product Information Sheets, SUPDIR 55 AMT 5, Expanded Programme on Immunization, World Health Organization, 1211 Geneva 27, Switzerland.
 Adduction d’eau potable avec pompe photovoltai’que – Pratiques et recommandations de conception et d’installation by Hubert Bonneviot, Fondation Energies pour le Monde.
 X. Vallve, et al., ‘Key parameters for quality analysis of multi-user solar hybrid grids (MSGs)’, 17th European Solar Energy Conference, Munich, Oct 2001.
 Perseus Guide (see Bibliography).
 Provided ventilation is adequate to avoid heating by the greenhouse effect.
 J. Agredano, et al., ‘Hybrid systems: the Mexican experience’, Proceedings of PV Hybrid Power Systems Conference, Aix-en-Provence, Sep 7-9, 2000.
 The expression ‘per day’, when referring to consumption or solar radiation, always means ‘per period of 24 h’.
 As the flowmeter and the GSM will not operate at the same time.
 Estimated retail price excluding tax early 2008.
 We will not enter into financial detail, but simply point out that the investment required for the installation we will describe would certainly not be affordable for this family with its modest income. Programmes of rural electrification have existed in Morocco for some time and financial incentives are available.