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Assumptions

Our savings calculator estimates what you could save by switching to a One Big Switch special offer.

Tariffs listed in the calculator are current "On Market" offers effective 14 October 2015.

The calculator only works in basic estimation mode whereby you enter:

  • whether you live in an urban or rural area,
  • who your provider is (if known),
  • what plan you’re on (if known), and
  • your last energy bill spend.

The calculator assumes that you have a single rate meter and you are on a 24 Hour tariff.

The single rate meter only provides a single number for the energy used. The rate you pay may vary by season or amount of usage (block tariff) but not by time of day.

If you do not know what your current meter type is please confirm with your current energy provider.

Please note that any recent adjustments in rates may not yet be incorporated into the comparison calculator. Refer to your Electricity and Gas retail contract to confirm your applicable rates.

  • How do we estimate your energy consumption?

    Our calculator uses the energy spend you provide to estimate how much energy you have used over the period that you supplied us.

    Your usage estimate is then used to calculate the cost of your current electricity for the next 12 months. It uses your retailer’s most recently published pricing. The calculator also uses this estimate of energy usage to calculate how much you would spend on the comparison One Big Switch special offer. Any differences in yearly costs between plans are shown as either savings or additional costs.

    Where you have not provided a plan (ie you have chosen the Don’t Know/Unsure option) One Big Switch will assume you are on the standard plan for that retailer. If the standard rates for that retailer are not found then One Big Switch will use the Electric Ireland standard rates. In these cases the plan and/or rates assumed by One Big Switch may differ from your actual plan and/or rates and the indicated savings may not be reflective of your situation.

  • How do we estimate your first year savings or first year costs?

    We use your last energy bill spend to estimate how much you may potentially spend or save in the future

    Our calculator assumes you have a single rate meter and uses the energy spend and your current electricity plan to estimate how much energy you have used over the period that you have supplied us.

    We annualise your last energy bill spend if you provide us with a period less than a year.

    Our calculator uses your usage estimate to calculate the cost of your current electricity plan for the next 12 months; it uses your retailer’s most recently published pricing. The calculator also uses this estimate of energy usage to calculate how much you would spend on the One Big Switch special offer. Any differences in yearly costs between plans are shown as either savings or additional costs.

    Please see ‘What meter is assumed when I enter my energy spend?’

  • How do we estimate your energy spend?

    We annualise your last energy bill spend if you provide us with a period less than a year.

    If you informed us that your last energy bill spend was for a month or a quarter or other period of less than 12 months then we will annualise this spend or usage in making our calculations as follows:

    • for a quarterly amount we will multiply your spend or usage by 4
    • for a bi-monthly amount we will multiply your spend or usage by 6
    • for a monthly amount we will multiply your spend or usage by 12

    This gives us an indication of your annual energy spend. Patterns that can change depending on your seasonal energy use and from other factors are not taken into consideration.

    If your energy spend which you have informed us is of an unusually high or low spend or usage for that period then the estimate of your annual usage and estimated potential saving may be affected. It may be over or under estimated.

    For a more accurate comparison of your electricity we recommend you provide us with your yearly spend or usage. If you have two years’ worth of bills at your disposal we recommend you work out the average yearly spend and enter that amount into the calculator.

  • Our Savings Calculator assumes you have a single-rate meter.

    When you enter your last energy bill spend we assume that you are on a single rate meter. If you have a different meter type, our calculation may under / overestimate your usage.

    If you choose to switch, your new energy supplier will determine your correct meter type and bill you accordingly.

  • What meter is assumed when I enter my usage?

    We assume you have a single rate meter and all your consumption is on a 24 Hour tariff.

    Currently we assume you do not have Night Storage Heating. If the usage you provide includes Night Storage Heating then the savings calculator estimates may not be accurate.

  • How do we estimate your potential savings?

    We estimate your potential savings based on current energy plans and currently published energy rates.

    We use the currently published rates for your current energy retailer and the retailer/s providing the offer/s. We have not factored any rate changes into our calculator. The estimated potential savings are based upon each gas or electricity retailer’s current published rates/tariffs.

    If you are on a fixed-rate plan the current rates assumed by One Big Switch may differ from your actual rates and the indicated savings may not be reflective of your situation.

    Electricity retailers may change their prices at any time, and we try our best to keep our data as up to date as possible, however there may be changes from the last published pricing which will affect any potential estimated savings. As a consequence we are unable to predict how any future price changes or other new offers that might become available might impact on costs and potential savings.

  • If you don’t know your electricity plan we will make assumptions about the rates you pay.

    Where you have not provided a plan (i.e. you have chosen the Don’t Know/Unsure option) One Big Switch will assume you are on the standard plan for that retailer. If the standard rates do not exist for that retailer then One Big Switch will use the Electric Ireland standard rates. In these cases the plan and/or rates assumed by One Big Switch may differ from your actual plan and/or rates and the indicated savings may not be reflective of your situation.

  • What discounts and rebates do we include and exclude in our calculations?

    In calculating your potential savings, we include the following:

    • All discounts that are applicable to your particular plan or to the One Big Switch Special Offer are always included in the savings. Examples are direct debit discounts, ebill discounts and guaranteed discounts.
    • Cash-backs applicable to the One Big Switch special offer. If the One Big Switch special offer that you are comparing to does contain a cash back, then that amount will be included in the estimated savings figure.

    In calculating your potential savings, we don’t include:

    • Cash-backs available in the first year of your current plan (e.g. €40 credit off your first energy bill). It is assumed that the last bill amount does not have a rebate applied.
    • Gifts the retailer may provide (e.g. magazines / movie tickets, vouchers).
    • Exit fees that your current retailer may charge for breaking out of your contract.
    • Any costs associated with changing your meter (e.g. to/from prepay).

    Note: we assume all discounts are VAT inclusive.

  • We assume you will stay with your new retailer for a minimum of 12 months

    We calculate your estimated potential savings based on rebates that may require you to remain at least 12 months on any offered plan/s and that you stay with your new gas or electricity retailer for a minimum period of 12 months. Some bonuses or cash-backs only occur in the first year and discounts included in your new plan may decrease in subsequent years, so the potential savings you could receive in the second year might be lower. Before choosing a new energy provider you should consider whether you may or may not stay with that energy provider for several years and how this might impact on your potential savings.

  • What else should I do to estimate my potential savings?

    Our calculator is designed to provide a useful estimate of the potential savings associated with switching to any offer/s we provide to our members. The savings estimates are based on the assumptions outlined on this page and may under-estimate or over-estimate real outcomes.

    We recommend that you also use other information sources such as energy suppliers' websites and energy regulators’ websites to help you determine the right supplier and plan for your particular situation.

  • We assume your consumption is not low usage in any billing period.

    Some retailers apply low usage charges or rates if consumption in a given billing period is below a designated level. This savings calculation does not take into account low usage consumption charges or rates that your retailer may apply.