The applied approach splits the total load curves into shiftable and fix parts, where the shiftable power is assumed entirely redistributable over the day. When considering net production and demand profiles, net production can be represented as negative demand. The DSM strategy then refers to the more general case of valley-filling measures, leveling out demand sinks. Computationally, this means finding an optimal power level such that filled-in energy below this level equals the shiftable energy. This approach gives an upper level to the achievable load matching improvement through DSM.

Two cases (2a and 2b) are defined, where in the first case the shiftable demand is that from washing, drying and dishwashing appliances that could be easily rescheduled and involve relatively little user interaction. The second case involves all end uses except lighting, cold
appliances and undefined additional demand, and implies considerable violation of everyday routines.

2.2. Storage

A third option for increased load matching is introducing small storage units as buffers between the PV system and the distribution grid. To study the effect of such systems a simple battery model is applied. When the PV system overproduces power, the battery stores energy up to the battery capacity EUm. At net demand, the battery unloads energy with an efficiency kejf. State-of-charge limits for avoiding deep-charging are not included in the model. In the case studied here (case 3) a storage size EUm of 1 Wh/Wp is used and an efficiency kejf of 0.8.

3. Results