Micro-tubular solid oxide fuel cells (MT-SOFCs) have diverse applications including transportation, critical military missions, auxiliary power units or portable power generators. Especially portable power devices should be lightweight and quickly started, so that they have requirements of high thermal shock resistance, high power density per weight and self-sustaining operation. This work presents the design, fabrication methods and performance of multiple MT-SOFC stacks containing cells of 15cm² active electrode area. Extruded Ni-8YSZ anode supports are coated with 8 mol%Y₂O₃-stabilized ZrO2 (8YSZ) electrolyte and layers of La_0.8Sr_0.2MnO₃-8YSZ/La_0.6Sr_0.4Fe_0.8Co_0.2O₃ cathode through several coating and sintering processes. The employed stack design methodology enables to stack the cells more easily and to minimize the reduction of power density by assembling the cells into the stack. The stacks are tested for measuring the electrochemical performance at temperatures between 650-750^oC with hydrogen fuel. The maximum power density achieved at 750^oC is 470mW/cm², and the voltage degradation rate is 71mV/kh for 1000hours. The stacks are further integrated with a Palladium-Platinum catalysed partial oxidation reformer (CPOx), an afterburner and a heat exchanger to investigate the quick-starting capabilities with hydrocarbon fuels such as propane and butane. After starting the system integrated with the short-stack of four cells, it reached 800^oC within 12 minutes. The upscale system with the stack of 54 cells delivered 200W net power output at DC 10 volts.