Please correct this. HVAC with renewable energy Price of energy is been raised markedly during the economic crisis years, and it will continue raising after it as the fossil fuel stock is being run lower. For that reason, it is very important to find a new way that we use the energy, it is needed to find a more efficiency way. I’m talking here about one of the process which take more primary energy consumption for people, HVAC and production of DHW. HVAC means Heating, Ventilation and Air Conditioning, and it is used to keep a building in a comfortable temperature. DHW means Domestic Hot Water and it is a is a thermodynamic process that uses an energy source to heat water above in order to make it useful for cooking, cleaning, bathing, and so on. And apart from that, in industry, hot water and water heated to steam have many uses. In domestic buildings, the most common source used for heating is gas natural, a fossil fuel. The performance of this source is not very efficient, and I will talk here about a much more efficiency performance. That is geothermal energy performance by a geothermal heat pump. A heat pump allows us, by power consumption, heating the hot point cooling the cold point. As we are talking about heating and DHW, the GHP is used to transfer heat from the ground; and it can be also used for cooling, transferring heat from the building to the ground. In Madrid, where the ground has an average temperature of 17ºC, a GHP can work with a Coefficient of Performance up to 5. That means it permit to transfer 5 units of thermal energy per one unit of electrician energy. Using the ground resource instead of natural gas, it is possible to avoid CO2 emissions and reduce a 30% the cost of the energy in HVAC and DHW. Apart from the high efficiency provided by the Geothermal Heat Pump, there are other strong point, as this engine permits to get heating, cooling and Domestic Hot Water from the same engine. You only need one system to keep your building comfortable. Thanks for your collaboration!