Pv solar install the inverter in loft or garage

davidanddeirdre

Can I just throw my twopennorth in to this debate?

I decided to have the inverter for our ten panels 1.75kW nominal system put in our dining room for several reasons, and in retrospect this was a good decision for us. Reasons:

1. Our garage is nowhere near the panels.

2. The loft space is very cramped, difficult to access and gets quite hot in summer.

3. Our existing meter and consumer unit was in the dining room, so I had the new stuff installed under it and built a VENTILATED cupboard round it down to floor level, which provides a whole lot of new storage space underneath the electricals. Wife happy.

4. The inverter now provides a certain amount of home heating esp on sunny winter days. OK it could theoretically get a bit warm in the room in the summer but this did not provide any problems last year.

5. Lastly but not leastly, I can keep an easy eye on output. For example, when snow fell last Saturday, and lay on the panels, when the sun came out afterwards I noticed output was only less than 100 W (mega shading, enemy No 2 (after darkness) of Solar PV). We got out a stepladder and long brush, cleared the panels and output shot up to nearly 1000W in minutes.

larkim

Dave_Fowler wrote: »

The copy of the manual I was reading said maximum 50C too, but also said derated reduced output above 40C (or was it 42C? - can't remember)

Dave F

Yes, that was my reading - basically they say "never install somewhere likely to exceed 50degC", but they also say that de-rating occurs when > 40degC. I read this as meaning that when the sensors inside the inverter read > 40degC then de-rating occurs, rather than "when the ambient temps reach > 40degC".

Matt

grahamc2003

larkim wrote: »

Yes, that was my reading - basically they say "never install somewhere likely to exceed 50degC", but they also say that de-rating occurs when > 40degC. I read this as meaning that when the sensors inside the inverter read > 40degC then de-rating occurs, rather than "when the ambient temps reach > 40degC".

Matt

Yeah, but in all likelyhood, the sensors will, at least, be sensing the incoming cooling air temp at the bottom of the inverter - and that will be the ambient temperature.

The only concern about the hall location is the varying buzzing. It only buzzes when generating, and the level varies for as yet unknown (to me) reasons - strangely, it isn't related to output. It's almost always insignificant, but was reasonably loud, close up, for about 5 or 10 minutes this morning. At this highest loudness, it was about as loud as my PC. Atm, it's no problem, and even if it were in a living room it wouldn't be, but it may be a concern a few years down the line (the construction of transformers means sources of vibration (therefore noise) can increase over time). Boxing in is no problem from any cooling aspect, no need for a fan, just holes suitable placed to allow airflow - the air temp will never exceed 23/24 in our hallway. Otoh, there are big advantages (for me, and others) of its current location, as already posted.

My problem is shading due to trees not owned by me. It's sunny, I'm getting 500W atm (although my panels point SW) - a few hours ago (with the sun low and no tree shading) I was getting 800W, so I'd expect probably 1500W atm with no shading). Mine is 7 panel 1.75kW, Sunny Boy 1700, single string (can that inverter take 2 strings?).

Original quote was for a 3kW system, but after I accepted that, they couldn't install before 3 Mar due to 'needing an inmverter which they coudln't get hold of in time'. They proposed the 1.75kW system which I originally didn't think worthwhile in my situation (shading, sw roof, wife doesn't like panels etc), but then had a rethink and decided to go with it. (The salesman thought it not worthwhile!, and I agree from the financial aspect - being quite high in percentage terms (even at 21p), but not worth bothering with in absolute terms).

davidanddeirdre

grahamc2003 wrote: »

Yeah, but in all likelyhood, the sensors will, at least, be sensing the incoming cooling air temp at the bottom of the inverter - and that will be the ambient temperature.

The only concern about the hall location is the varying buzzing. It only buzzes when generating, and the level varies for as yet unknown (to me) reasons - strangely, it isn't related to output. It's almost always insignificant, but was reasonably loud, close up, for about 5 or 10 minutes this morning. At this highest loudness, it was about as loud as my PC. Atm, it's no problem, and even if it were in a living room it wouldn't be, but it may be a concern a few years down the line (the construction of transformers means sources of vibration (therefore noise) can increase over time). Boxing in is no problem from any cooling aspect, no need for a fan, just holes suitable placed to allow airflow - the air temp will never exceed 23/24 in our hallway. Otoh, there are big advantages (for me, and others) of its current location, as already posted.

My problem is shading due to trees not owned by me. It's sunny, I'm getting 500W atm (although my panels point SW) - a few hours ago (with the sun low and no tree shading) I was getting 800W, so I'd expect probably 1500W atm with no shading). Mine is 7 panel 1.75kW, Sunny Boy 1700, single string (can that inverter take 2 strings?).

Original quote was for a 3kW system, but after I accepted that, they couldn't install before 3 Mar due to 'needing an inmverter which they coudln't get hold of in time'. They proposed the 1.75kW system which I originally didn't think worthwhile in my situation (shading, sw roof, wife doesn't like panels etc), but then had a rethink and decided to go with it. (The salesman thought it not worthwhile!, and I agree from the financial aspect - being quite high in percentage terms (even at 21p), but not worth bothering with in absolute terms).

If the sun is high enough in summer to rise above the trees, then the overall effect of the shading may not be too dramatic. We also have a 1.75kW system facing abt 10deg E of SE, so our panels get shading developing from the roof ridge/chimney stack c. 2to 3 hrs after midday, depending on time of year, after which output plummets on sunny days. Despite that in the first year which ends shortly we will have exceeded the prediction for this area by abt 200 units, giving a return of c. 11% including bill saving. Much better than an ISA!
If the trees are really near at hand, you might also have a problem on cloudy days due to a general reduction of light levels. If it is really bad, can you offer to pay for lopping and keep the wood for logs (quite a lucrative business these days it seems)?

Martyn1981

grahamc2003 wrote: »

The only concern about the hall location is the varying buzzing. It only buzzes when generating, and the level varies for as yet unknown (to me) reasons - strangely, it isn't related to output. It's almost always insignificant, but was reasonably loud, close up, for about 5 or 10 minutes this morning. At this highest loudness, it was about as loud as my PC. Atm, it's no problem, and even if it were in a living room it wouldn't be, but it may be a concern a few years down the line (the construction of transformers means sources of vibration (therefore noise) can increase over time). Boxing in is no problem from any cooling aspect, no need for a fan, just holes suitable placed to allow airflow - the air temp will never exceed 23/24 in our hallway. Otoh, there are big advantages (for me, and others) of its current location, as already posted.

The pull of PV is strong in this one. Welcome to the dark side, Master Luke.

So to summarise,

To avoid any overheating issues, you avoided the loft (a large loft?), but want to place it in a small box.

The buzzing isn’t bad now, when it’s maybe only peaking for 20% of an hour, but that’s probably due to low sun angle, short days, and shading. What happens when you get a good week in the summer, the sun’s high and it’s running at peak all the time. After all there’s a huge difference between 12 mins and 7 days!

Hope Mrs GC2003 doesn’t get tinitus and come after you with a rolling pin.

Too cheeky? or

Mart.

don0301

grahamc2003 wrote: »

Yeah, but in all likelyhood, the sensors will, at least, be sensing the incoming cooling air temp at the bottom of the inverter - and that will be the ambient temperature.

The only concern about the hall location is the varying buzzing. It only buzzes when generating, and the level varies for as yet unknown (to me) reasons - strangely, it isn't related to output. It's almost always insignificant, but was reasonably loud, close up, for about 5 or 10 minutes this morning. At this highest loudness, it was about as loud as my PC. Atm, it's no problem, and even if it were in a living room it wouldn't be, but it may be a concern a few years down the line (the construction of transformers means sources of vibration (therefore noise) can increase over time). Boxing in is no problem from any cooling aspect, no need for a fan, just holes suitable placed to allow airflow - the air temp will never exceed 23/24 in our hallway. Otoh, there are big advantages (for me, and others) of its current location, as already posted.

My problem is shading due to trees not owned by me. It's sunny, I'm getting 500W atm (although my panels point SW) - a few hours ago (with the sun low and no tree shading) I was getting 800W, so I'd expect probably 1500W atm with no shading). Mine is 7 panel 1.75kW, Sunny Boy 1700, single string (can that inverter take 2 strings?).

Original quote was for a 3kW system, but after I accepted that, they couldn't install before 3 Mar due to 'needing an inmverter which they coudln't get hold of in time'. They proposed the 1.75kW system which I originally didn't think worthwhile in my situation (shading, sw roof, wife doesn't like panels etc), but then had a rethink and decided to go with it. (The salesman thought it not worthwhile!, and I agree from the financial aspect - being quite high in percentage terms (even at 21p), but not worth bothering with in absolute terms).

so why did you proceed?

you've argued for months against solar pv?

jimjames

I had the same concern about the location of our inverter. Originally planned to be located in our loft but this gets very hot and due to loft conversion space remaining is quite limited. Garage would have been a possible option but needed concrete digging to get a route so indoor cupboard was also considered.

I rejected the idea due to the possible noise but also again a limited space that could heat up in summer. Finally decided to mount it on the outside wall and built a vented cabinet around it. It is on an shaded east facing wall so hopefully will remain cool even in summer.