Optimal bidding

For each market in which you have assets participating, axle formulates an optimal bidding strategy. These bids (also called offers) are proposals to flex demand up or down, at a certain price.

If a bid is accepted, in most markets you will receive an availability payment.

If assets are then called upon to provide the procured flex, we will use the callbacks you provided to instruct your assets to change their power.

For more details on how we instruct assets, see the Add an asset page.

What do we use to calculate bids?

  1. Prices: The prices available in that market. In some markets these are published ahead of time. In others we forecast prices.

  2. Flex Forecast: Our forecasted availability for your pool of registered assets.

  3. Remuneration structure: Some markets pay for availability, others for energy. This, and the penalty for failing to provide procured flexibility, affects the optimal bidding strategy.

Why do we place multiple bids?

Flexibility markets vary widely in structure. For some markets, we will submit a portfolio of bids, at different volumes and prices. These reflect our assessment of the risk of obtaining varying levels of flex.


We are very confident of supplying 1MW of flex based upon our forecast. We place a bid at our forecast market price for 1MW of flex. We expect this to be accepted, and have little uncertainty about our ability to fulfill the bid.

Based upon our forecasts, we’re 80% confident we’ll have another 0.5MW available. However, since we run a higher risk of not meeting the requirements should we be called, we need to bid in at a higher price to counterbalance the increased risk of penalty should we fail to meet the procured volume.

Submitting bids

You can review the bids for a pool at the optimal bids endpoint.

During testing, you can take these bids and submit them yourself via the place bids endpoint. You can review outstanding bids via the get bids endpoint.

Once you’re comfortable, we’ll enable autobidding for your account. We’ll automatically calculate the optimal bids, place them, and collect payment on your behalf.