Abstract: High temperature proton exchange membrane fuel cells (HTPEMFCs) and solid oxide fuel cells (SOFCs) can generate both electric power and heat due to their high operating temperatures. The high temperature fuel cells attract lots of attention particularly for off-grid applications with demand of cogeneration. One major issue regarding with such fuel cell-based cogeneration systems is the supply of fuel gas. Compressed or liquid hydrogen storage equipment is not practical due to the technical difficulties. A possible solution is to produce hydrogen on-site by steam reforming of liquid fuels. The HTPEMFCs can tolerate carbon monoxide in the fuel gas up to 3% because of the high operating temperature in the range of 160-200 oC. Therefore, the reformate produced by steam reforming of methanol can be directly fed into HTPEMFCs as fuel gas. The multichannel micro packed bed reformer developed in our lab can efficiently generate syngas with about 74% H2, 25% CO2, and 1% CO in the dry reformate. Fuel flexibility is one major advantage of SOFCs, and CO is considered as a fuel instead of a harmful composition because SOFCs usually operate in temperatures between 700-1000 oC. Steam reforming of heavy hydrocarbon fuels such as gasoline and diesel can be directly combined with SOFCs for cogeneration. Our lab developed a compact monolithic reformer for SOFCs. Reforming of n-hexadecane (C16H32) at 800 oC can produce a dry syngas with about 70% H2, 15% CO, 15% CO2 and <1% CH4. The syngas was supplied to a 100W SOFC stack and power was successfully generated.