Ten "Rules-of-Thumb" to Select Better Hydroelectricity Projects
Dec 20, 2011 1:11 PM EST
By Institute for Environmental Diplomacy and Security, Univ. of Vermont
Guest post by Dr. Robert Goodland
Comments and corrections to: RbtGoodland@gmail.com
1. Adopt Best Practice
Follow ï¿½Best Practiceï¿½ to the fullest extent possible. This includes
utilizing best technology, as per rule 10 below. All dam proponents
and financiers need an environmental and social policy. Much best
practice for hydro selection, planning, construction, monitoring
(starting with adequate pre-project surveys which are required if
progress is to be measured), including panels of social and
environmental experts, is well codified by the World Commission on
Dams (2000). Follow best practice throughout the Environmental and
Social Impact Assessment (ESIA) process -- beginning with adequate pre-
project demographic, environmental, health, and socio-economic
baseline surveys ï¿½ and then throughout construction, operations, and
decommissioning. Teams who have worked in any one country should
uphold or strengthen standards when working on dams in foreign
countries; avoid double standards.
2. Perform regional planning
Reduce environmental impacts by cramming many dams on the fewest
rivers in a country or region. Often, the first dam imposes most of
the impact of a cascade of dams. But scrutinize social risks
beforehand. Interpolating one more dam to a cascade generally is lower
impact. The highest impacts would be to site a single dam on each of
the nationï¿½s rivers. Interpolation of a dam between two existing dams
or shortly upstream of an existing dam greatly reduces the impact of
the new dam. The first dam on a river normally has the biggest
impact, compared with the impacts of subsequent dams on the same river.
3. Rehab existing projects before new projects
Rehabilitate, refurbish, renovate or upgrade existing hydros before
going ahead with new hydros. Adding new turbines or replacing old
turbines with more efficient or bigger ones are almost always much
lower impact than building new dams. Rehabs should normally be well
in hand before a new dam is contemplated, just as energy conservation
and demand management should be well in hand before new generation is
permitted. For example, it has been calculated that 70,000 MW could be
developed in the USA by rehab alone, with no new dams. Now that
Venezuelaï¿½s Guri hydro complex, Nigeriaï¿½s Kainji and the Zambia/
Zimbabwe Kariba hydros, for example, are several decades old, they are
being usefully upgraded with low impacts.
5. Dam tributaries before the mainstem
Develop dams on tributaries before dams on the mainstem. If a
mainstream dam is necessary based on comprehensive options assessment,
it should be sited as far upstream as feasible. That will often impose
less impact. Outstream diversions may be high impact.
6. Uphold Human Rights, especially Free Prior Informed Consent
Seek free prior informed consent from stakeholders, as well as
meaningful consultation. Reject any use of force, and reject any
measure that would be involuntary. Choose sites with little or no
need for resettlement. All resettlement must be strictly voluntary
(UN FPIC). As soon as oustees consent to their move, it should proceed
expeditiously. Oustees must promptly become better off project
beneficiaries as soon after their move as possible. If the dam is
built and owned by Indigenous People or ethnic minorities (e.g.,
Canadaï¿½s Minashtuk Hydro) other rules will apply.
Avoid conflict zones and militarized areas. Ensure effective grievance
mechanisms and respect for human rights. All potentially impacted
stakeholders (upstream, reservoir basin, downstream, and other
(including those living along transmission lines and project roads)
must be consulted and participate in decisions affecting them from the
options assessment stage, to get away from a project-centered
perspective, thru pre-feasibility and construction and afterwards.
7. Promote irrigation before electricity
Many dams are labeled ï¿½multipurposeï¿½ nowadays, suggesting that the
purpose of the dam in question includes more than one purpose, such as
generation of electricity, flood control, water supply, fisheries,
navigation and irrigation. This can be misleading because in
operating the dam, power generation is almost always the topmost
priority, as compared to secondary uses such as irrigation.
Electricity generation earns by far the most revenue. Some of this
revenue is best allocated to promoting other uses, such as irrigation.
Most so-called ï¿½multipurposeï¿½ dams indeed have more than a single
purpose, but the other purposes are subsidiary to power generation.
In many poor rural areas, water to grow food is much more important
than electricity. Irrigation often depends on water storage during the
wet season for release during the lean season. While it is possible
for irrigation to be combined with hydro in multi-purpose schemes,
there are often inherent incompatibilities between generation of
electricity and provision of irrigation water when water is scarce but
most needed during the dry season. When dam operators must choose one
over the other, electricity generation almost always trumps
irrigation. This is important in several ways, especially when in
contrast to hydro electricity generation, there are few alternatives
to irrigation dams, and agricultural intensification is much needed as
world population may exceed 9 bn by 2050.
8. Manage both climate mitigation and climate adaptation
All new dam designs nowadays need a thorough greenhouse gas (GHG)
emissions assessment. Choose low emissions designs. Dams likely to
emit as much GHG as a coal-fired equivalent should not be developed.
Conversely, dams likely to emit less GHG than a gas-fired equivalent
should be promoted. Reduce the amount of biomass in the reservoir
before filling. More than 27 European nations and Australia, and many
jurisdictions (e.g., Vancouver) now mandate a charge for GHG
emissions. Hydro must internalize its GHG emissions in project design
and cost/benefit analysis.
The best hydros will be designed to take climate change into account.
Hydros are designed based on the best historic river discharge data
obtainable. Now climate change has arrived, the best hydros will be
designed using the most reliable predictions of climate change on the
future of river flows. Extreme events (heavy rains, storms, droughts)
may become more frequent. Appropriate adaptation strategies will
include diversified and decentralized investments, to avoid putting
all eggs into one basket in a time of increasing hydrological
9. Conserve Biodiversity
Choose sites with little or no valuable biodiversity habitat (such as
tropical forest). Lower the dam height or move the dam to minimize
forest loss. If some forest loss cannot be avoided, finance
compensatory offsets that provide better benefits than the area
inundated. Conservation units (e.g. National Parks, UN World Biosphere
Reserves, UN World Heritage sites, protected forests) should normally
always be avoided.
10. Reduce reservoir size and minimize hydraulic head
Optimize the potential of hydrokinetic turbines or non-dam hydro.
Select no-head, ultra-low head (c.3 m), and micro-hydro ï¿½ all before
higher-head hydros. Hydros in which the reservoir fills the riverbed
up to the annual wet season level are usually low impact. In the
paramount tradeoff between reservoir area and impacts, reduce
reservoir area by optimizing flow (by tube turbines), and reducing
head, preferably to zero. Select engineering (e.g., by kinetic
turbines) to reduce the size of the reservoir area.
Pithy ï¿½Rules-of-Thumbï¿½ suffer from simplification and these are no
exception. Although these Rules-of-Thumb apply only to
hydroelectricity dams, and not to irrigation dams, they would also all
apply with minor revisions to most development projects (except # 10,
which is entirely hydro-specific). These Rules-of-Thumb apply only to
hydroelectricity dams which supply about 20% of world electricity, and
for which there are many alternate sources of electricity,
particularly renewables (e.g., solar, wind, wave). They apply mainly
to big dams, rather than to microhydro, which impose lower impacts.
The ï¿½Rules-of-Thumbï¿½ are offered mainly to hydro designers, hydro
financiers and those seeking to reduce the impacts of big hydro.
Renewable energy is fast becoming more feasible as climate change,
democracy and biodiversity are accorded more importance.
The author, Robert Goodland, served the World Bank Group as
environmental adviser for 23 years, where he drafted and persuaded the
Bank to adopt its current mandatory social and environmental
ï¿½Safeguardï¿½ policies. He helped set up the World Commission on Dams in
Cape Town. After retirement, he was the Technical Director of the
independent Extractive Industry Review of the World Bankï¿½s oil, gas
and mining portfolio (EIR.org). He was elected chair of the Ecological
Society of America (Metropolitan), and President of the International
Association for Impact Assessment. Last year he was awarded IUCNï¿½s
Coolidge Medal for outstanding lifetime achievement in environmental
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