A portable heat and electricity generating device comprising: - an enclosure comprising openings for fuel feed, combustion air intake, exhaust gas outlet and an electricity outlet, - within the enclosure there are provided an intake channel for combustion air, a combustion chamber and an electricity generating element, - a heat transfer element extending to the combustion chamber to distribute the heat further from the combustion chamber, when the device is in use, - a fire grate in the combustion chamber for fuel material to be located for combustion, wherein the device further comprises: - the fuel feed opening is located above the combustion chamber so that the fuel feed is gravity based, - a heat sink is provided in the intake channel for pre-heating the combustion air before combustion, - the electricity generating element is a thermoelectric element provided between the heat sink and the heat transfer element, • wherein the intake channel is located parallel to the combustion chamber and the direction of the air flow in the intake channel is configured opposite to the direction of the combustion/exhaust gas, • characterized in that, • the grate is provided with two inclined mesh structures located in the opposite part of the enclosure and forming a ridge, wherein the angle of inclination is within a range of 15° to 60° and said grate is below the fuel feed, and configured to prevent fuel F from falling to the air intake channel. - an enclosure comprising openings for fuel feed, combustion air intake, exhaust gas outlet and an electricity outlet, - within the enclosure there are provided an intake channel for combustion air, a combustion chamber and an electricity generating element, - a heat transfer element extending to the combustion chamber to distribute the heat further from the combustion chamber, when the device is in use, - a fire grate in the combustion chamber for fuel material to be located for combustion, - the fuel feed opening is located above the combustion chamber so that the fuel feed is gravity based, - a heat sink is provided in the intake channel for pre-heating the combustion air before combustion, - the electricity generating element is a thermoelectric element provided between the heat sink and the heat transfer element, • wherein the intake channel is located parallel to the combustion chamber and the direction of the air flow in the intake channel is configured opposite to the direction of the combustion/exhaust gas, • characterized in that, • the grate is provided with two inclined mesh structures located in the opposite part of the enclosure and forming a ridge, wherein the angle of inclination is within a range of 15° to 60° and said grate is below the fuel feed, and configured to prevent fuel F from falling to the air intake channel. • wherein the intake channel is located parallel to the combustion chamber and the direction of the air flow in the intake channel is configured opposite to the direction of the combustion/exhaust gas, • characterized in that, • the grate is provided with two inclined mesh structures located in the opposite part of the enclosure and forming a ridge, wherein the angle of inclination is within a range of 15° to 60° and said grate is below the fuel feed, and configured to prevent fuel F from falling to the air intake channel.