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The European Union's directive of the energy performance of buildings makes energy systems with local energy generation interesting. To support local energy generation the government has appointed a commission to investigate the possibility to implement net metering for grid connected PV-systems. In this paper three different systems are simulated and analyzed with regards to economics and energy: a PV-system and a heat pump (alternative 1), a heat pump and a solar thermal system (alternative 2) and a heat pump, a PV-system and a solar thermal system (alternative 3). System alternative 1 is profitable with daily net metering and monthly net metering and unprofitable with instantaneous net metering. The solar electrical fraction of the system is 21.5%, 43.5% and 50%, respectively. System alternative 2 is unprofitable and has a solar electricity fraction of 5.7%. System alternative 3 is unprofitable and has a solar electricity fraction of just below 50. The conclusion is that a PV system in combination with a heat pump is a superior alternative to a solar thermal system in combination with a heat pump.

The incentives for PV-systems in Europe is being gradually lowered or ended. This makes a higher level of self-consumption interesting for owners of PV-systems.Sweden has an incentive of 35% of the investment cost for PV-systems. Unfortunately not all consumers can get this incentive. Therefore a high level of self-consumption will be necessary if the PV-systems are to be profitable in Sweden.A reference system with two different energy storage technologies is investigated in this paper. One system with 48. kW. h of batteries and one system with a hot water storage tank where the electricity is stored as heat.The research questions in this paper are:. Which storage system gives the highest level of PV electricity self-consumption?Are the storage systems profitable with the assumptions made in this paper?What are the levelized costs of electricity (LCOE) for the reference system with different storage system?The system with batteries has a self-consumption of 89% of the annual PV-electricity output and the system with a hot water storage tank has 88%.The system with batteries has a levelized cost of electricity two times higher than the system with a hot water storage tank.

The building sector in Europe and Sweden accounts for a large part of the total European electricity end use. A large fraction of Swedish buildings are equipped with heat pumps for heating and a combination of heat pumps and decentralized energy generation from photovoltaic systems is an interesting system solution for reducing the energy use. It is important that the building has a high self-consumption of the generated PV-electricity. Self-consumption can be seen as energy conservation and has a considerable higher economic value than exported electricity for the building owner.

A ground source heat pump with a novel weather forecast controller is simulated in Trnsys and compared to a reference case in regards to self-consumption and profitability. The economic analysis is based on the annuity method and a sensitivity analysis regarding annual cost, discount rate and annual electricity price change has been performed.

The results indicates that the increase in self-consumed photovoltaic electricity is limited to 7% with the proposed novel weather forecast controller, which means that the controller is unprofitable. Because of this the proposed novel forecast controller is not a viable way of increasing self-consumption in systems with photovoltaic systems and ground source heat pumps in Sweden.

This paper presents an in-depth analysis on how exhaust air- and ground source- heat pumps in combination with PV-systems affects the specific energy demand of buildings with the proposed new Swedish near zero energy building definition. It also present a method on how to estimate the contribution from the photovoltaic-system on the reduction of the specific energy demand of the building.

A challenge with the proposed near zero energy building definition is that it is not clearly defined how it manages photovoltaic electricity as a mean to reduce the specific energy demand of buildings. The size of the specific energy demand reduction is, amongst other things, depending on the number of loads in the building and in which assumed sequence the different loads utilizes the photovoltaic electricity.

The results suggest that the building with the ground source heat pump has the lowest specific energy demand. In terms of self-consumption fraction the two heat pump types is fairly equal but the ground source heat pump has a larger solar energy fraction.

The difference between the two photovoltaic electricity usage assumptions used in this article is 6 kWh/m2 for both the GSHP and EAHP Buildings.