By 2021 all new buildings in the EU will be nearly Zero Energy Buildings (nZEB). IEA HPT Annex 49 will investigate the design and integration of heat pumps in nZEB to derive energy- and cost-optimized systems. First results on the state-of-the-art for single family nZEB in Switzerland reveal that future requirements of the cantonal building directive MuKEn 2014 also reach the more ambitious energy label MINERGIE® for most systems. The high performance building label MINERGIE-A® requires a balance of entire weighted consumption and weighted on-site solar PV electricity on an annual basis. This requirement, though, is so strong, that there are no incentives for optimization, e.g. an increase of electricity self-consumption by batteries, since this will lead to higher system cost. First conclusions presume that omission of this PV requirement can lead to similar energy performance, but lower system cost as well as less grid interaction and higher flexibility.