The appliance setup would be a litlle complex.Perhaps a forced air electric furnace, with a hot watercoil (like the A coil for AC), connected to an oil and a gas boilder, with a heat exhanger for DHW, connected to a storage tank with electric heat elements.

You'd have to purchase/maintain at least 3 boilers/burners,and have the appropriate one come on line based on spot rates.

Oil would be different, since you keep a stock of that, rather than receive it as you use it, like gas or electricity. You might have a kind of meter to montor oil useage, so that a local (your tank) shortage will deafult to other energy sources until the tank gets re-filled (which the order could go out when oil prices are adequately low)

Also, you'd need near instant reportback of the meters, to account for the savings you'd make on not using energy at high spot prices.