Objective: Mitigation Sectors: Renewable energy Collection

Table 2. Comparison in financial requirements between five PV systems and five diesel pump systems of increasing size. Source: (Odeh, Yohanis & Norton, 2006)

System	Total Capital Costs (US$)	Total Operating Costs (US$/year)	Total costs over a 10-year period	Total costs over a 20-year period
PV 1 (2800 Wp)	18 188	600	24 188	30 188
PV 2 (4500 Wp)	27 470	800	35 470	43 470
PV 3 (6300 Wp)	37 398	900	46 398	55 398
PV 4 (10 000 Wp)	56 800	1400	70 800	84 800
PV 5 (15 000 Wp)	82 000	1600	98 000	114 000
Diesel 1 (3.5 KVA)	3840	5642	60 260	116 680
Diesel 2 (4.5 KVA)	4720	5864	63 360	122 000
Diesel 3 (6.3 KVA)	6050	6029	66 340	126 630
Diesel 4 (10.0 KVA)	8350	6307	71 420	134 490
Diesel 5 (15.0 KVA)	10 320	6593	76 250	142 180

Clean Development Mechanism market status
Currently, there are no registered CDM projects using solar water pumps. However, two solar water pump projects were in the CDM pipeline. Of these, one got rejected and the other was withdrawn from the process. In both cases, this was because the methodology that was chosen was incompatible with the project description.
Solar water pump projects, however, certainly have the potential to be eligible for CDM registration and funding. The baseline for GHG emissions in the absence of such a project would be based on a diesel powered pump. A solar water powered pump would therefore reduce GHG emissions which would generate CDM credits.
For calculation of these GHG emission reductions, it is recommended to apply the approved methodology for Mechanical energy for the user with or without electrical energy (AMS-I.B. version 10). This methodology helps to determine a baseline for GHG emissions in the absence of the project (i.e. business-as-usual circumstances), how emission reductions below this baseline can be calculated, and how these reductions can be monitored. General information about how to apply CDM methodologies for GHG accounting can be found at: [[1]].
However, close attention should be paid to the project description to ensure compatibility between the project and the methodology. This methodology considers mechanical energy for the direct user, and is therefore not compatible with a project that delivers water to several users. For example, a project that irrigates multiple fields with the same installation should not use this methodology.
References

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  Firatoglu, Z., Yesilata, B., (2004). New approaches on the optimization of directly coupled PV pumping systems. Solar Energy 77, pp. 81-93.
  
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  IEA (International Energy Agency) 2010. Technology Roadmap - Solar photovoltaic energy
  
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  IPCC 2010. Special Report on Renewable Energy Sources and Climate Change Mitigation, In Press.
  
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  NYSERDA, (2004). Guide to Solar Powered Water Pumping Systems in New York State. New York State Energy Research and Development Authority. Retrieved from: [[2]]
  
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  Odeh, I., Yohanis, Y., G., & Norton, B., (2006). Economic Viability of Photovoltaic Water Pumping Systems. Solar Energy Vol 80 (2006) pp. 850-860.
  
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  Posorski, R., (1996). Photovoltaic water pumps, an attractive tool for rural drinking water supply. Solar Energy 58, pp. 155 - 163.
  
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  Short, T., Oldach, R., (2003). Solar Powered Water Pumps: the Past, the Present - and the Future. Journal of Solar Energy Engineering 125 (1), pp. 76 -82.
  
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  Short, T.D., & Thompson, P., (2003). Breaking the Mould: Solar Water Pumping - the Challenges and the Reality. Solar Energy 75 (2003) pp 1-9.
  
• 
  REN21. 2010. Renewables 2010 Global Status Report (Paris: REN21 Secretariat).