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    DOS Frequently Asked Questions (FAQ)

    What is Demand Opportunity Service?

    Demand Opportunity Service (DOS) allows customers connected to the grid to draw additional power over and above the amount they are contracted for. The service is interruptible and available only when there is surplus transmission capacity.

     

    Market participants need to qualify for DOS by submitting an application, Schedule A and Schedule B and being approved by the AESO. 

     

    What is the advantage of DOS?

     

    Once approved to take service under Rate DOS, a customer can utilize surplus transmission capacity at a reduced cost for planned maintenance or to pursue economic opportunities. Under Demand Transmission Service (DTS), exceeding the contract capacity could affect the customer's ratchet level (see current ISO tariff for more information) for up to two years. 

     

    Who benefits from DOS?

     

    All users of the Alberta Interconnected Electrical System (AIES) benefit when DOS is properly used. The revenues from DOS are applied towards lowering overall transmission costs and no additional transmission infrastructure is built to serve DOS customers. 

    Who is eligible to use Rate DOS?

    Existing DTS customers and market participants who have applied for system access service under Rate DTS may be eligible to utilize additional electric energy under DOS once they have been qualified. Qualifying to use the rate does not guarantee that DOS will be available.

    What is involved in the DOS application process? 

    To apply for DOS, please fill out and submit the application form, Schedule A and Schedule B.

    A non-refundable application fee of $10,000 is required.  Upon receiving a market participant’s completed application documents, the AESO will assess their eligibility and notify them of the outcome within 90 days.

     

    The AESO is currently developing a DOS information document to assist those wishing to apply and will post this on the website as soon as it is available.  

    When should I apply for DOS?

    Market participants seeking to connect to the transmission system can apply for DOS:

    ·     in parallel with submitting their System Access Service Request (SASR)

    ·     after they have applied for system access service; or

    ·     once they are connected (existing customers).

     

    Please note that identifying on the SASR that you intend to apply for DOS provides the AESO with visibility of your intent to apply for DOS. Rate DOS must be applied for separately and approval is not guaranteed.

    How is DOS priced?

    There are two Rate DOS options:

     

    DOS Dispatchable
    ·    considerably less than the $/MWh cost of Rate DTS

    DOS Term
    ·    noticeably more expensive than the $/MWh cost of Rate DTS
    ·    used exclusively for planned maintenance and the potential avoidance of setting a new ratchet level if DTS contract capacity is exceeded   

    How does the AESO determine whether there is sufficient capacity?

    When the AESO receives a qualification application for DOS, a study will be undertaken to ensure sufficient capacity exists for DOS without negatively affecting the operation of the power system. This is usually in the form of a power flow study using parameters that conform to the approved policies of the Western Electricity Coordinating Council.

    Can I use Rate DOS without having a (or applying for) a DTS contract?

    No, having a DTS contract is a requirement for DOS qualification. If you are applying for DOS concurrently with DTS, the DOS approval, if granted, will be conditional on executing the DTS contract at a later date. 

    Is there a minimum DTS contract amount required?

    The AESO has not prescribed what the minimum amount of DTS should be but suggests that a market participant contract enough DTS to maintain station service at their site. Market participants are encouraged to set their DTS contract capacity or firm service amount at a level that would still allow them to operate if DOS capacity is unavailable. 

    How does the AESO enforce the eligibility requirements?

    New applications for DOS must contain sufficient information so that the AESO can assess whether the customer's circumstances meet the commercial and technical eligibility criteria, as spelled out in the DOS terms and conditions. Customers are also required to sign an undertaking that they will notify the AESO if there are any material changes to their eligibility after they have been approved to take service under Rate DOS. The AESO may also audit a customer's eligibility from time to time, as outlined in the DOS terms and conditions.

    When is DOS curtailed on the transmission system? 

    In instances where transmission system capacity is unable to sustain DOS load or the Alberta balancing authority lacks sufficient ancillary services, demand opportunity service will be recalled before firm service provided under Rate DTS or Rate FTS.  

    What happens if the customer does not comply with a direction or directive to curtail DOS load in a timely manner? 

    A DOS user that does not comply with a directive to curtail DOS may be deemed to have demonstrated their ineligibility for DOS. In such cases, the AESO, in its sole discretion, may revoke the customer's approval for Rate DOS and bill all subsequent metered energy delivered to the market participant under Rate DTS.