8 research outputs found
Empirical evidence on the potential of rainwater harvesting for residential water supply in Accra
We evaluate the potential of rainwater harvesting for residential water supply by estimating, analysing and comparing the per capita water consumption accessible from rainwater harvesting (RWH) systems and that acquired from water tanker services (WTS) for single-family households in Accra, Ghana. Although the values from WTS stochastically dominates those from RWH over a wide range, the difference in their mean values does not appear to be statistically significant, and the probabilities that the per capita water consumption, of a household selected at random, exceeds the WHO service levels of {5, 20, 50, 100} lpcd are {1.000, .937, .239, .0474} for RWH, compared to {1.000, .994, .555, .0467} for WTS. We conclude that for single-family dwellings in Accra, the WHO service levels for water consumption and hygiene obtainable from RWH is appreciable and comparable to those from WTS providers. Therefore, households can satisfy their current water consumption levels with RWH alone
Statistical analysis of water storage capacity and days-storage for single-family households in Accra
In order to evaluate whether installed water storage capacity for single-family households in Accra are large enough to harness the full potential of rainwater harvesting (RWH), we compare this capacity, and its associated days storage, with that required for RWH, and examine the relationship between roof area, household size and each of these storage capacities. Results show that (1) installed capacity is 25.6 m3 significantly smaller, and more varied, than that required for RWH; (2) consequently, the associated days storage for installed capacity is 110 days significantly smaller, and more varied, than that for RWH; (3) unlike the capacity for RWH, which had a significant relationship with only roof area, there was no significant relationship between roof area, household size and installed capacity. We conclude that the decision on installed storage capacity ignores the potential of RWH, thereby, making it smaller than what is required to harness this potential
Management of sewerage system: case study in Tema
Many sanitation systems in most developing countries have deteriorated resulting in a lower level of service
and consequent deterioration of environmental conditions. The sewerage system in the Tema Municipality is
not different from other developing countries; three pumping stations and the treatment plant have been shut
down hence raw sewage flows through a by-pass into the sea without treatment, creating an environmental
hazard. This study examined the problems associated with the management of the sewerage system in Tema
Municipality through field visits, administering questionnaires and interviews with key stakeholders. The
study revealed that Tema Metropolitan Assembly (T.M.A) lacks key personnel; equipment, logistics and
funds to manage the system. 33% of the residents using the sewer lines are not billed; the tariffs paid by
the industries are low. The revenue does not march Operation and Maintenance cost and current electrical
energy cost make up 64% of the Operation and Maintenance cost
Learnings from implementing the excreta flow diagram (SFD) process in Kumasi
Excreta, Faecal or Shit Flow Diagrams (SFDs) are away to clearly represent how excreta flows along
the sanitation service chain. This approach has already gained popularity and many SFDs have already
been produced. To date little attention has been paid to the methods and data used, or the credibility of
the SFDs. The SFD Promotion Initiative has created a tool to enable the wider roll-out of SFDs, which
includes a credibility assessment. The product is a report on service delivery context with an embedded
SFD. This briefing paper discusses the lessons learnt from trialling the tool and process developed
through this initiative, in the city of Kumasi (Ghana). The most important lesson learnt is that
stakeholder engagement is critical not only for obtaining credible data, but also for validating the SFD
produced
Partnership approach to capacity building for IWRM, West Africa
Partnership approach to capacity building for IWRM, West Afric
Presentation_1.PDF
<p>To address national and global low-carbon fuel targets, there is great interest in alternative plant species such as cassava (Manihot esculenta), which are high-yielding, resilient, and are easily converted to fuels using the existing technology. In this study the genes encoding hyperthermophilic archaeal starch-hydrolyzing enzymes, α-amylase and amylopullulanase from Pyrococcus furiosus and glucoamylase from Sulfolobus solfataricus, together with the gene encoding a modified ADP-glucose pyrophosphorylase (glgC) from Escherichia coli, were simultaneously expressed in cassava roots to enhance starch accumulation and its subsequent hydrolysis to sugar. A total of 13 multigene expressing transgenic lines were generated and characterized phenotypically and genotypically. Gene expression analysis using quantitative RT-PCR showed that the microbial genes are expressed in the transgenic roots. Multigene-expressing transgenic lines produced up to 60% more storage root yield than the non-transgenic control, likely due to glgC expression. Total protein extracted from the transgenic roots showed up to 10-fold higher starch-degrading activity in vitro than the protein extracted from the non-transgenic control. Interestingly, transgenic tubers released threefold more glucose than the non-transgenic control when incubated at 85°C for 21-h without exogenous application of thermostable enzymes, suggesting that the archaeal enzymes produced in planta maintain their activity and thermostability.</p
Table_1.PDF
<p>To address national and global low-carbon fuel targets, there is great interest in alternative plant species such as cassava (Manihot esculenta), which are high-yielding, resilient, and are easily converted to fuels using the existing technology. In this study the genes encoding hyperthermophilic archaeal starch-hydrolyzing enzymes, α-amylase and amylopullulanase from Pyrococcus furiosus and glucoamylase from Sulfolobus solfataricus, together with the gene encoding a modified ADP-glucose pyrophosphorylase (glgC) from Escherichia coli, were simultaneously expressed in cassava roots to enhance starch accumulation and its subsequent hydrolysis to sugar. A total of 13 multigene expressing transgenic lines were generated and characterized phenotypically and genotypically. Gene expression analysis using quantitative RT-PCR showed that the microbial genes are expressed in the transgenic roots. Multigene-expressing transgenic lines produced up to 60% more storage root yield than the non-transgenic control, likely due to glgC expression. Total protein extracted from the transgenic roots showed up to 10-fold higher starch-degrading activity in vitro than the protein extracted from the non-transgenic control. Interestingly, transgenic tubers released threefold more glucose than the non-transgenic control when incubated at 85°C for 21-h without exogenous application of thermostable enzymes, suggesting that the archaeal enzymes produced in planta maintain their activity and thermostability.</p
Image_1.JPEG
<p>To address national and global low-carbon fuel targets, there is great interest in alternative plant species such as cassava (Manihot esculenta), which are high-yielding, resilient, and are easily converted to fuels using the existing technology. In this study the genes encoding hyperthermophilic archaeal starch-hydrolyzing enzymes, α-amylase and amylopullulanase from Pyrococcus furiosus and glucoamylase from Sulfolobus solfataricus, together with the gene encoding a modified ADP-glucose pyrophosphorylase (glgC) from Escherichia coli, were simultaneously expressed in cassava roots to enhance starch accumulation and its subsequent hydrolysis to sugar. A total of 13 multigene expressing transgenic lines were generated and characterized phenotypically and genotypically. Gene expression analysis using quantitative RT-PCR showed that the microbial genes are expressed in the transgenic roots. Multigene-expressing transgenic lines produced up to 60% more storage root yield than the non-transgenic control, likely due to glgC expression. Total protein extracted from the transgenic roots showed up to 10-fold higher starch-degrading activity in vitro than the protein extracted from the non-transgenic control. Interestingly, transgenic tubers released threefold more glucose than the non-transgenic control when incubated at 85°C for 21-h without exogenous application of thermostable enzymes, suggesting that the archaeal enzymes produced in planta maintain their activity and thermostability.</p