Solar panels on just an east facing roof?

littlegreen

I've been thinking about getting solar panels for a while, however our main roof has a dormer on the west side, and velux on the east. Therefore I thought about having 5 or so panels on the south facing extension.

I've had someone come to quote and, as our south facing roof is split and the opp end of the house to the electrics, they've suggested putting 6 or 7 panels below the velux on the easy facing roof. Thoughts?

Wfh so easy for us to move electric use to morning bar the evening meal. Low users too circa 2000kwh a year. For us it is more about eco efficiency then reduction in bills but obviously don't want to fork out for a system that is going to take ridiculously longer to pay back.

Screwdriva

Depending on the dormer construction, they too can be used to install flat roof mounted panels (see image below).

Even with a pure East facing aspect, the total annual generation can be very impressive, so I would agree with the recommendation but would recommend panelling every inch of the available roof surface area on the S/ W/ E aspects. I would skip a battery if any installer recommends one though. 

A 12 bifacial panel SolarEdge system will cost ~£6K fully installed. You will likely need optimizers or Microinverters with a multiple aspect, complex roof design. 

littlegreen

Screwdriva said:

Depending on the dormer construction, they too can be used to install flat roof mounted panels (see image below).

Even with a pure East facing aspect, the total annual generation can be very impressive, so I would agree with the recommendation but would recommend panelling every inch of the available roof surface area on the S/ W/ E aspects. I would skip a battery if any installer recommends one though. 

A 12 bifacial panel SolarEdge system will cost ~£6K fully installed. You will likely need optimizers or Microinverters with a multiple aspect, complex roof design. 

Thanks very much, helps a lot. Unfortunately our dormer is right on the ridge line but good to know re east facing.

Surveyor today recommended no battery and I agree, usage is too low plus it would take up quite a considerable part of a small garden! Keen to see quote come back now so we can look to book in!

Katiehound

littlegreen said:

 

Wfh so easy for us to move electric use to morning bar the evening meal.  

Don't forget that you could be running a slow cooker during the day- uses very little electricity- and your evening meal would be (partly) ready for you using solar.
 I see there is at least one model where you can brown the food first in the pan & then put in the s.c. (Morphy Richards sear & Stew)

Exiled_Tyke

I tend to agree with @Screwdriva on this one.  I'd use every inch of available E,S & W space you can to maximise quantity and spread (through the day) of production.  In which case you will need either microinverters or a SolarEdge system.  Or more than one inverter! 

However I was advised not to put panels on top of my flat roof (only one installer's opinion mind) because it will lead to complications when the roof needs replacing (mine has an expected life of about 20 years) and the anchoring with added weight could create potential puddles in the roof increasing risk of leakage in time.  I can't attest to the validity of these statements, just passing on what was said to me. 

Screwdriva

Exiled_Tyke said:

However I was advised not to put panels on top of my flat roof (only one installer's opinion mind) because it will lead to complications when the roof needs replacing (mine has an expected life of about 20 years) and the anchoring with added weight could create potential puddles in the roof increasing risk of leakage in time.  I can't attest to the validity of these statements, just passing on what was said to me. 

Van Der Valk kits do not have anchorings/ fixings to the roof but they are designed to be weighed down in place (designs/ weightage arrives from VDV directly). If the flat roof is structurally sound, it should be able to take the weight of a flat roof mount. The only way to know for sure is via an in person survey. 

Exiled_Tyke

yeah It was the weights that I was told would create pressure points and would be best avoided 

Screwdriva

Exiled_Tyke said:

yeah It was the weights that I was told would create pressure points and would be best avoided 

That's the first time I've heard of this but I can see it happening on a very weak structure. No complaints of this in the field as the weight is often evenly distributed.

94JDH

Screwdriva said:

Exiled_Tyke said:

yeah It was the weights that I was told would create pressure points and would be best avoided 

That's the first time I've heard of this but I can see it happening on a very weak structure. No complaints of this in the field as the weight is often evenly distributed.

I have 35 No. of my panels using this Van Der Valk system - that photo is crying out for some side panels!

Screwdriva

94JDH said:

I have 35 No. of my panels using this Van Der Valk system - that photo is crying out for some side panels!

Spot on - this was mid installation.