During the last two decades, the concept of eco-efficiency has been recognized as a suitable
measure of progress towards a greener and more sustainable economy. The prefix
“eco-” refers to both economic and ecological (environmental) performance. The need for
improving eco-efficiency leads to the challenge of identifying the most promising alternative
solutions which improve both the economic and the environmental performance of a given
system (“eco-innovations”). Therefore, it becomes critical to develop eco-efficiency metrics for
measuring environmental and economic performance of a system. The current paper presents
a methodological framework that attempts to explore the use of eco-efficiency indicators in
meso-level water use systems and through them to assess the impact of innovative technologies
in such systems. The assessment of the environmental performance follows a life cycleoriented
approach using the midpoint impact categories while the economic performance is
measured using the total value added to the product due to water use. The eco-efficiency is
expressed as the ratio of the economic performance indicator to the environmental performance
indicator. The proposed approach is applied to a water use system of the agricultural
sector, and more specifically to the fresh form tomato crop production in Phthiotida. The
analysis reveals that the most important environmental impacts of the system are (a) greenhouse
gas emissions due to energy consumption, (b) release of toxic substances, due to the use
of fertilizers and pesticides, and (c) depletion of freshwater resources. Three alternative interventions
are examined for upgrading the value chain: (a) installation of subsurface drip irrigation
(SDI) system, (b) replacement of diesel pumps with solar pumps, and (c) use of organic
fertilizers. Based on the findings, all of the proposed interventions have a positive impact on
the overall eco-efficiency of the system. SDI is the least favorable mainly due to its high investment
cost. The use of solar pumps strongly influences climate change and photochemical
ozone formation while the use of organic fertilizers has a more balanced impact on all indicators,
with an emphasis on eutrophication. Thus, for a more holistic approach, regarding the
eco-efficiency performance, a combined application of these three scenarios may be proposed.