Widespread misconceptions about residential PV

March 17, 2023 Sandra Enkhardt

From pv journal Germany

Family demand for rooftop PV programs and residential batteries continues to develop. In an effort to meet the expectations of house owners, Verbraucherzentrale NRW – a German shopper affiliation – is making an attempt to make clear false expectations about PV installations that would disappoint prosumers.

“You will need to concentrate on the private targets of utilizing photovoltaics after which to search out out extra. On this manner, disappointments might be prevented and solar energy can be utilized actually effectively,” stated Sören Demandt, a digital power transition analyst for Verbraucherzentrale NRW.

The primary false impression is to vow those that they’ll change into self-sufficient with PV programs and storage programs. This isn’t true, as a result of PV programs and residential storage options can solely cowl a sure proportion of annual electrical energy provides for households.

The diploma of self-sufficiency that may be achieved is between 25% and 90%, relying on the extent of energy consumption and whether or not storage has been put in. Particularly within the winter months, the quantity of solar energy that may be generated is much from ample, so grid energy needs to be bought, stated Demandt. Full self-sufficiency can solely be achieved with extra seasonal storage, resembling hydrogen.

“Nevertheless, that’s technically complicated and hardly makes financial sense for a residential unit,” stated Demandt.

One other false impression pertains to the assumption {that a} PV system is just worthwhile together with a battery. Some householders appear to imagine that feeding solar energy into the grid isn’t a financially engaging choice.

“A photovoltaic system is financially worthwhile, even with out storage,” stated Demandt. “If putting in a battery along with the photovoltaic system is doable, it will depend on a variety of elements – primarily, a house’s consumption profile and electrical energy prices.”

Owners ought to subsequently examine their self-consumption ranges with out storage. They will evaluate increased self-consumption ranges via battery storage with precise electrical energy prices.

Verbraucherzentrale NRW additionally rejects the concept south-facing rooftops are all the time higher for PV programs than east-west-facing rooftops. It isn’t nearly producing as a lot solar energy as attainable, however producing electrical energy when it’s wanted. The annual yield of a PV system on an east-west roof is just round 80% in comparison with a south-facing roof. Nevertheless, the yield from photo voltaic programs on east-west roofs might be unfold over the course of a complete day, because the programs nonetheless get a big quantity of solar within the morning and night.

Many individuals who do not need rooftops for PV installations typically contemplate investments in plug-in photo voltaic units. These might be connected to balconies or arrange in gardens. Nevertheless, if tenants hope to have the ability to energy family home equipment resembling espresso machines, they could be upset.

“These panels are notably appropriate for overlaying the baseload within the family,” defined Demandt. “The electrical energy is used immediately – for instance, for a phone, an web router, or an alarm clock radio.”

If extra energy is required, will probably be supplied by the grid. That is the case, for instance, with a espresso machine that briefly requires round 2,000 W to warmth up water. Balcony PV modules alone couldn’t obtain this, in response to Verbraucherzentrale NRW.