Sounds somewhat fishy to me:
"Der Bauherr möchte in der gemeinsamen Tiefgarage mindestens 20 Ladesäulen für Elektroautos installiert haben. Eine entsprechende Ladesäule kann bei Schnellladung einen Strom von 32 A liefern. Das heißt, würden alle Ladesäulen voll in Betrieb gehen, müsste ich theoretisch 640 Ampere vorhalten. Das geht natürlich nicht."
He is stating it categorically that allocating additional 640A max draw is not possible for a 20 homes apartment complex. Why not? He doesn't explain why, and it's not true, as later parts of the article make it clear.
32A extra capacity per apartment will cost extra money - but 20 new apartments complex with garage space is a big 7-8 figure construction investment already, and unless they are in a really problematic place (historic part of town with limited free power capacity left) a (3x) 32A requirement is basically the max draw of air conditioning, or of a heat pump - another (3x) 16A for home appliances, often more if it's large luxury homes. If any of the apartments can also be used for commercial purposes the power draw might be even higher.
I don't know the capacity prices and regulations for NRW, but power capacity is usually a one time sum paid to the utility during the permitting and connection procedure of the new power lines, with occasional requirements like having to lay a cable directly to the nearest transformer. Utilities also have a financial interest in increasing power consumption - more income to them. So they'll be accommodating, unless constrained by unusual circumstances out of their control.
So the extra power should usually not be a problem unless in historic quarters, and costs can be easily recouped through the significant home value increase of a high capacity home EV charging station. Apartment owners can also charge tenants extra for the charging capacity in the garage.
The pain he is describing with sharing power between charging columns sounds legit from an engineering point of view - but he should not have gone there and never explains why they didn't purchase enough power capacity for each apartment to begin with.
He explains some of this:
"Nebenbei bemerkt, auch für diese Leistung hätte ein kleiner Trafo installiert werden müssen, da sich das Grundstück zwar auf Stadtgebiet aber mehr auf der „grünen Wiese“ befindet. Bei Großstädten wäre diese Leistung – je nach Lage – aber noch im Netz vorhanden."
So they'd have to have installed a small transformer. That's actually often cheaper and faster than getting permits and lay new ground cable to an existing transformer 1-2 km away...
He indicates that he couldn't convince the developer that more power is required:
„Das muss ich den Bauherren erklären und kann es nicht“
TLDR: incompetence, ignorance. Competing developers will be able to sell their better equipped apartments at higher prices.
Thanks! IMHO not OT because this is FUD slowing the adoption of BEVs in Germany.
It looks not only like FUD but wrong-headedness about the nature of home charging.
Looking a bit closer at this:
“Now, in a new housing development (about 100 apartments in 12 houses) the following happened. The client wants to have installed at least 20 charging stations for electric cars in the common underground car park.”
So,
- Instead of including a dedicated outlet of some standard variety at each parking space, they planned to offer a small number of “charging station spots”, maybe 20 0f these for 100 apartments. Because one would have to move into and out of these spots instead of leaving the car there for the night, they wanted to make them “fast charging”.
- This seems altogether a terrible idea. No one wants to have a fueling station in the corner of a parking garage that you have to drive back and forth to from your assigned spot. The whole convenience of BEVs is tied to “park it for the night and plug it in”. It also probably means that the building owner would have pay for all use of these stations, instead of being able to bill the electricity to each apartment.
- I think they calculated that they would need 32a for each of these “common” charging stations to justify them being “fast” and therefore ok to share. Again that seems a stretch to call that “fast”, and why not 20a for every spot instead. More total capacity but can be billed to each apartment.
- I suppose it could be that they didn’t even plan to have assigned parking spots, just a key card to get in and out, and open parking. Note that this is “about 100 apartments” spread across 12 structures, so unclear whether it is one large underground garage under all of the buildings (probably 12 with 8 apartments each), or 12 separate underground garages, but I am assuming for cost reasons that it must be one big garage for all.
- Apparently it never occurred to the builder to just supply a moderately-powered outlet for each parking space, BUT the garage may be designed like a commercial shopping mall garage, where lots of spaces are out in the open and not near any support columns where power can be attached.
- ABOVE says to me that it is hard to claim that these are “luxury” apartments, which I am pretty sure I read somewhere, especially my suspicion that the garage is just a sea of open area with painted lines and unassigned spots.