The use of photovoltaic (PV) systems for powering heat pumps (HP) leads to an economic, energy efficient and environmentally friendly alternative for heating and cooling generation. A technical solution developed by the authors permits stand-alone configurations to operate without batteries, mitigating up to 75% of the solar power fluctuations resulting from cloud-passing. Once its technical feasibility has been demonstrated, the economic potential of this innovative solution should be assessed (avoiding a battery system is a significant advantage). This paper presents a comparative economic assessment of this autonomous (AU) solution and a self-consumption (SC) solution, that would substitute a grid-powered HP system for the space heating and cooling of two livestock farms located in Spain. Results show that PV-HP systems are economically feasible regardless of the technical solution: the Profitability Index (PI) is in the 2.23–2.97 €/€ range, the Internal Rate of Return (IRR) is in the 8.1–10.9% range, the Payback Period (PBP) is in the 9.2–11 years range and the savings in terms of the Levelized Cost of Energy (LCOE) are in the 57–70% range. The AU solution offers a higher economic profitability, because it permits larger savings in the electricity bill. The SC solution presents lower LCOEs because of its greater electricity production.