Chemical heat accumulator

A chemical heat accumulator for heating an object using heat of reaction generated when first reactant and second reactant are reacted with each other to produce a compound and for storing heat by separating the compound into the first reactant and the second reactant using external heat generated outside of a system of the reaction, the chemical heat accumulator comprising:

• first- to Mth-stage heat storage units, in which M is an integer equal to or greater than 2, wherein the respective heat storage unit including:
• a reaction vessel housing the first reactant and a regeneration heat exchanger that heats the compound by the external heat;
• a container housing the second reactant;
• and
• a connection passage connecting the reaction vessel and the container with each other for guiding the second reactant housed in the container to the reaction vessel, the connection passage being provided with an opening/closing member capable of opening and closing the connection passage;
• and
• a condensing part configured to condense the second reactant in a gas state produced when the compound is separated in the reaction vessel of the respective heat storage unit, wherein
• the reaction vessel of the Mth-stage heat storage unit is thermally connected with the object, and
• the reaction vessel of a (N−1)th stage heat storage unit is thermally connected with the container of an Nth-stage heat storage unit, in which N is an integer equal to or greater than 2 and equal to or less than M.