• Small Hydro

    Energy Alternatives for Newfoundlandand and Labrador

    [Return to Policy Summary Page]

    The proposed Muskrat Falls power project in Labrador will produce approximately 824 MW (million watts) of power and the current oil fired generator holyrood has a capacity of 490 MW. A reduction in pollution and fuel costs by replacing the oil fired plant with power from Labrador is one of the proposed benefits. Newfoundland does not currently have a shortage of power and won't unless the population decline is reversed.

    Newfoundland and Labrador Hydro commissioned a study in 1986 to conduct an inventory of the potential small hydro resources and found a total of 850 MW in small hydro schemes available on the island that could be connected to the existing power grid. Of this, 172 MW supplied by 22 plants had very good cost/benefit ratios -- i.e. they would likely economical. The report was written by SHAWMONT NEWFOUNDLAND LIMITED, the same engineering firm that built the Bay d'Espoir hydroelectric power station.

    Rather than assume the risk of a six billion dollar mega project like Muskrat Falls in Labrador and add to this the expensive of power connections from Labrador to Newfoundland and from Newfoundland to Nova Scotia, it would far less risky to develop small hydro on the island, as needed. It is also possible that it will never be needed, but if the population decline ceases, generation stations could be added as electrical demand grew.

    The report is huge and contains a great deal of topographic maps, but the introduction and conclusions are pasted below, and there is a pdf attached here which contains the executive summary, conclusions and a list of the sites. A full copy is housed in the Memorial University Queen Elizabeth II library.

    Labrador Coastal Power

    Another report was commissioned in 2009 to look at the alternative energy potential of coastal Labrador. It concludes "Hatch’s Review of Hydraulic Potential of Coastal Labrador identified numerous potential sites with estimated cost of energy less than that of diesel generation. In addition, some opportunities were identified that possessed sufficient energy at low cost to completely replace one or more diesel plants. With the identified opportunity for the interconnection of Charlottetown, Port Hope Simpson, and Mary’s Harbour it is possible that three plants could be eliminated, making a larger plant more viable."

    The question that needs to be asked of Nalcor and the Newfoundland and Labrador government is this: Why is small hydro being ignored while risky mega projects are promoted?

    If the answer for not developing the Island's potential is environmental, then why is it ok in Labrador?

    Note: this is part of a larger article on Newfoundland's Energy Options.

     


    (this is an OCR conversion of the scanned report so that Google can index it -- please read the document linked above for a more accurate rendition).

    AN INVENTORY OF SMALL HYDRO SITES
    FOR ENERGY SUPPLY TO THE ISLAND GRID
    VOLUME I
    METHODOLOGY & FINDINGS

     

    1. INTRODUCTION
    1.1 Background
    Nature has generously endowed the Island of Newfoundland with the
    landforms, abundant and evenly distributed precipitation which
    favour the development of small scale hydro electric schemes
    (capacity between 1 MW and 20 MW). Although many studies of individual
    small hydro schemes have been carried out in recent years,
    as yet no comprehensive survey of the entire Island has been
    undertaken. It was the objective of this study to undertake a
    comprehensive survey of hydro power resources on the Island of
    Newfoundland and to compile an inventory of small hydro sites
    which may be economically developed within the foreseeable future.

    1.2 Scope of Work
    Newfoundland and-Labrador Hydro's Terms of Reference called for an
    inventory survey of small hydro schemes meeting the following
    guidelines:
    (a) the study were to be limited to schemes with capacities
    ranging from 1 MW to 20 MW (schemes greater than 20 MW
    were to be identified but not analysed),
    (b) the study was to consider only those schemes .which could
    be economically connected to the existing Island transmission
    system,
    (c) small hydro sites previously studied were to be excluded,

    1.2 Scope of Work (Cont'd)
    (d) the following areas were to be excluded:
    Gras Marne National Park
    Terra Nova National Park
    Bay du Nord River, Main River and Terra Nova River basins
    (e) potential environmental impacts were to be noted, but no
    further investigations undertaken.

    1.3 Authorization
    This study was authorized by L. G. Sturge, Manager of Engineering,
    Newfoundland and Labrador Hydro and confirmed by means of Purchase
    Order #66505 dated May 30, 1986 following acceptance of ShawMont's
    proposal of April 30, 1986.

    EXECUTIVE SUMMARY
    A comprehensive survey of small scale hydro sites on the Island
    of Newfoundland was undertaken in this study. The purpose of
    this survey was to compile an inventory of small scale hydro
    sites ( 1 MW - 20 MW) which could be feasibly connected to the
    existing Island power grid. This survey encompassed the entire
    Island, with the exception of the following areas:
    Gros Morne National Park
    Terra Nova National Park
    Bay du Nord, Main and Terra Nova river basins.

    It was based primarily on topographical information taken from
    1:50,000 topographic mapping, regionalized hydrologic
    relationships and standardized conceptual plant layouts.
    Extensive use was made of the SHYDRO computer model -and other
    computational aids to f_aci li tate the examination of the very
    large number of sites involved.

    Site investigations also included examination of the advantages
    of significant watershed diversion, upstream storage
    developments and group developments .

    Altogether a total of 198 sites were selected for cost analysis,
    from which 160 were found to be potentially feasible,
    benefit/cost ratios > 1.0. Of this number, seven sites were
    judged to be very attractive <B/C > 2.8) and probably feasible
    under current economic conditions. Fifteen sites were relatively
    attractive (B/C 2.2- 2.8) and possibly feasible under current
    economic conditions; while the remaining 138 sites may be
    feasible at some future date. These results are summarized in
    Table 3 .1.

    In the analyses all plants were assumed to operate as
    run-of-river plants and were treated essentially as "fuel
    savers" for the purposes of economic evaluation .

    EXECUTIVE SUMMARY (Cont'd)
    The results of analyses of the benefits of upstream storage
    developments, watershed diversions and group developments are
    .shown in Tables 3.5, 3.6 and 3.7, respectively. These results
    confirm that substantial economic advantages may be obtained
    from including these features in the scope of small scale hydro
    developments.

    RECOMMENDATIONS
    The following recommendations are noted to assist Hydro in
    planni_ng the next phase of the investigation into Small Scale
    Hydro potential on the Island. It is recommended:
    (i) that more detailed investigations be carried out on all
    si.tes having benefit/cost ratios greater than 2.2 with
    priority given to sites with B/C > 2.8. Such
    investigations should include, as a minimum, preparation
    of 1:2000 scale maps with 2m contours from aerial
    photos, API, site reconnaissance (walk-over) visits and
    preliminary environmental evaluation:

    ( ii) that investigations should be on a group basis where
    several sites are close together or form a natural unit;

    (iii) that possibilities for upstream storage and watershed
    diversions be further reviewed. [In areas where access
    to upstream structures is difficult, consideration
    should be given to innovative design and construction
    approaches 1 such as use of winter roads I transport by
    all terrain vehicles, etc.].


    (iv) that the advantages of providing additional storage to
    permit operation ·of plants to maintain a significant
    level of firm monthly energy production be investigated
    [Under the assumed run-of-river mode of operation many
    plants would be out-of-service during periods of low
    flow, which often occur during winter months when system
    capacity and energy demands are at their maximum].

    3. FINDINGS
    3.1 Preamble
    The methodologies applied in this study were designed to meet the
    standards normally expected in prelilninary studies: that is, to
    provide order of magnitude estimates of costs and benefits of
    sufficient accuracy to reasonably separate potentially feasible
    schemes from non-feasible schemes.

    As noted previously, the unit cost assumed for civil works were
    based on assumed average conditions, that might be optimistic in
    some cases. In instances, where site conditions were known to be
    much different from average, suitable adjustments to unit costs
    have been made: however the majority of site analyses were based on
    "average" unit costs.

    Economic feasibility was evaluated from benefit-cost analyses in
    which annual costs were based on an effective interest rate of 6% =
    1. 5% to cover insurance, interim replacement and 0 & M: while
    annual benefits were evaluated at a "levelized" rate of 60
    mills/kWh, in constant 1986 dollars, as suggested by Hydro. Schemes
    having benefit/ cost ratios greater than 1. 0 were considered as
    being potentially viable. The above economic assumptions, imply a
    relatively high evaluation of benefits and optimistic estimates of
    cost, due to ommission of the usual conservatism in unit cost
    estimates. The resulting benefit/cost ratios may thus be regarded
    as giving optimistic assessments of Island hydro potential.

    It should be emphasized that these benefit-cost ratios are only
    intended to provide a relive ranking of site feasibility and should
    not be taken as absolute indicators of economic feasibility.
    However, for this type of study, it was judged preferable to err on
    the optimistic side so that the inventory of sites obtained would
    comprise a complete list of all sites which could be ultimately
    viable within the foreseeable future.


    3.2 Environmental Observations
    The Terms of Reference for this environmental assessment of hydro
    study did not include detailed sites: but requested only that
    potential environmental problems be identified where-ever possible.
    In most of the areas studied the major environmental problem would
    be adverse impacts on salmon habitat. Such impacts could include
    obstruction of salmon migration routes, inundation and/or silting
    of salmon spawning areas and reduction in flows on schemes
    involving watershed diversions. Where sites were upstream of
    spawning areas or inaccessible to migrating salmon, there should be
    no adverse impact on salmon habitat; accordingly, environmental
    problems related to salmon, were only identified <*in Tables 3.1
    and 3.2> at sites on sections of river accessible to salmon
    r typically at sites on the lower sections of the larger rivers].
    Data collected in the "Catalogue of Rivers in Insular Newfoundland"
    by Porter et al, Environment Canada <Fisheries & Marine Service>,
    1978 was used to identify areas of salmon habitat.

    3.3 Site Analysis
    Each site analysis comprises a data sheet<s>, cost analyses and, in
    the case of sites having B/C ratios > 1. 0, a site map showing a
    schematic layout of the scheme is also included. Potential
    environmental problems and other observations or suggestions were
    also noted on the data sheet<s>. In essence, each such compilation
    is a miniature engineering report. These miniature reports are
    filed by Hydrologic Region and compiled in Volume II of this
    report.


    3.4 Discussion of Results
    The main objective of this study was to produce an inventory list
    of all potentially feasible small hydro schemes [lMW - 20MW] which
    could be economically connected to the existing Island power grid
    [including the proposed transmission line into the Hope Brook
    Mine]. The entire Island, excluding the Gros Morne and Terra Nova
    National Parks, Bay du Nord, Main River and Terra Nova river
    basins, was searched for potential small hydro schemes. A total of
    198 sites were selected for preliminary cost analysis of which 160
    were found to be potentially feasible [with B/C ~ 1]. These sites
    are listed in Table 3.1 in descending order of benefit/cost ratio .

    Hydro schemes analysed and found to be infeasible [with B/C < 1.0]
    are listed in Figure 3.2.

    In order to facilitate interpretation of the results, Table 3.1 has
    been sectioned by drawing two lines through it, one corresponding
    to a benefit cost ratio of 2. 80 with the other corresponding to
    2.2. The lines permit classification of the results as follows:

    "B/C > 2. 8 sites very attractive, probably current economic conditions
    feasible under current economic conditions

    B/C 2.2- 2.8 sites relatively attractive, possibly feasible under
    current economic conditions


    B/C 1.0 - 2.2 sites that may be feasible in the future .

    The first of these dividing lines <B/C = 2. 2) assumed "current" interest
    a"levelized" energy value dollars, as suggested by rate of 12% [+1.5% of 50 mills/kWh, Hydro. The second was based· on an for 0 · + M ] and in constant 1986 line <B/C = 2.8) assumes, in addition, a contingency of +30% on project capital cost to allow for unfavourable site conditions and prices.

    On the basis of this classification, seven schemes were judged to
    be very attractive, a further fifteen to b~ relatively attractive
    and 138 to be marginal .

    3.4 Discussion of Results (Cont'd)
    For the sake of completeness, small hydro sites previously studied
    [and therefore outside of the scope of work of this study] are
    listed in Table 3. 3: while sites larger than 20 MW are lis ted in
    Table 3.4, which includes sites previously studied as well as
    several large sites identified for the first time, in this study.

    The post-glacial topography of the interior of the Island offers
    many opportunities for development of upstream storage reservoirs
    or watershed diversions: but, as previously noted, only relatively
    large upstream storage and watershed diversion schemes were
    studied. In cases where diversion schemes robbed water from
    neighbour'ing plants, the pros and cons of such divers ions
    were investigated and only those diversions where the benefits
    outweighed the losses* were included in the final site analysis .

    The results of analyses of upstream storage and watershed diversion
    schemes are summarized in Table 3.5 and 3.6 (details are included
    with the corresponding ·site analyses in Volume II). As can be seen
    in these summaries the benefit/cost ratios of upstream storage and
    watershed diversion schemes can be very high and thus substantially
    improve economics of the related hydro sche.mes .

    In areas where several sites are located close together
    substantial economic advantages may be obtained by group
    development since common facilities such as access roads,
    transmission lines, construction camps, etc. may be shared among
    several sites.


    * Where B/C ratio of diversion was-greater than B/C ratio of
    neighbouring plant/plants.

    3.4 Discussion of Results (Cont'd)
    Several such groupings have been evaluated, on an approximate
    basis, using SHYDRO and the results are summarized in Table 3. 7.
    Two facts emerge from an examination of Table 3.7.

    (i) the advantages of group developments tend to be more
    substantial at remote sites and

    (ii) several group developments have combined installed
    capacities and energy outputs in excess of 30 MW and 140
    gWh per annum approaching the same order of magnitude as
    some "large" hydro sites.

    3.5 Conclusions
    On the basis of this inventory study it is estimated a total
    potential of 850 MW in small hydro schemes may be available on the
    Island within reach of the existing Hydro power grid. Of this
    total, 172 MW in 22 plants is considered to be relatively
    attractive in terms of current benefit and cost parameters. The
    most attractive sites are generally to be found on the Northern
    Peninsula, West and South West coasts, where topographic relief is
    greatest.

    The following recommendations are noted to assist Hydro ~n planning
    the next phase of the investigation into Small Scale Hydro
    potential on the Island. It is recommended:

    ( i) that more detailed investigations be carried out on all
    sites having benefit/cost ratios greater than 2.2 with
    priority given to sites with B/C > 2.8. Such investigations
    should include, as a minimum, preparation of 1:2000cale
    maps with 2m contours from aerial photos, API, site
    reconnaissance (walk-over) visits and preliminary
    environmental evaluations:

    Conclusions (Cont'd)
    (ii) that investigations should be on a group basis where
    several sites are close together or form a natural unit:

    (iii)that possibilities for upstream storage and watershed
    diversions should be further reviewed [In areas where
    access to upstream structures is difficult, consideration
    should be given to innovative design and construction
    approaches, such as use of winter roads, transport by or
    all terrain vehicles, etc.]

    (iv) that the advantages of providing additional storage to
    permit operation of plants to maintain a significant level
    of firm monthly energy production be investigated [Under
    the assumed run-of-river mode of operation many plants
    would be out-of-service during periods of low flow, which
    often occur among winter months when system capacity and
    energy demands are at their maximum].



     

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