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So now I have a solar PV system how do I make the most of it???
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With only six panels what am I likely to generate? I am just outside Glastonbury, south facing, panels are at roof pitch (about 40 degrees).
Panels come in a variety of sizes, but even if they are as large as 260 kWp, that would only give a maximum expected output of around 1.5 kW.
At this time of year if you have a look at the display around 1 pm on a clear sunny day, that will be pretty close to your maximum.
Your problem in making use of this power is that pretty much all your standard loads - washing machine, dishwasher, immersion, will comfortably exceed this, even without allowing for a little base load.
Kit is available to control and modulate the immersion load, but on such a small installation is probably uneconomic, and not really suitable for a property you don't own.
Once you have an estimate of panel rating, you can plug your figures into a performance calculator here: http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php0 -
It does indeed have a little flashing light, but as a self confessed geek, I need more than that!
If you can get access to the cable (either the positive or neutral lead) between the inverter and the fuse box you could fit an Owl power monitor - the Micro+ should be fine and is pretty cheap. This will tell you what you are generating any time of the day.
I note that someone said that 1500W isn't ideal, as most appliances are more than that (washing machines, dishwashers and kettles tend to be about 2,200W) which is true, but that is to look at the issue from the wrong side. If you have an appliance taking power, then view it as an opportunity to soak up all of the power you are generating. Use appliances one after the other and never two at the same time - at least that way you maximise your solar contribution.4kWp, Panels: 16 Hyundai HIS250MG, Inverter: SMA Sunny Boy 4000TLLocation: Bedford, Roof: South East facing, 20 degree pitch20kWh Pylontech US5000 batteries, Lux AC inverter,Skoda Enyaq iV80, TADO Central Heating control0 -
I note that someone said that 1500W isn't ideal, as most appliances are more than that (washing machines, dishwashers and kettles tend to be about 2,200W) which is true, but that is to look at the issue from the wrong side. If you have an appliance taking power, then view it as an opportunity to soak up all of the power you are generating. Use appliances one after the other and never two at the same time - at least that way you maximise your solar contribution.
Fair comment, I tend to be a little blinkered by having E7, so the mental calculation has also to consider if it would be more economical if run at night. The small amount of money saved on each occasion must be remembered - the dishwasher tablets cost about the same as the power!
I find the Eco-Eye monitor to be quite helpful, as it has the option of showing a real time graph on my computer.
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Thanks for all the info so far!
I only guessed it was a 1600W inverter based on the number of panels and assuming they are 250W. I think I will go up into the loft again and try to find the type number on it.Given it's a 1600w inverter I'd say it's highly likely there are 6 x 250w panels being 1500w.
This is what we have been doing so far.:DOther than making use of high consuming electrical appliances when the sun is out just enjoy the fact that you have some free electricity and haven't had to pay for it!
Luckily our appliances are new and mostly efficient, I made sure when I purchased them because we were living in an all electric flat at the time. The washing machine is A+++ rated and the fridge freezer is A++ rated, we don't use a dishwasher, and have no immersion heater. The highest rated appliances will be the oven and tumble drier.Your problem in making use of this power is that pretty much all your standard loads - washing machine, dishwasher, immersion, will comfortably exceed this, even without allowing for a little base load.
Thanks for the link.Once you have an estimate of panel rating, you can plug your figures into a performance calculator here: http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php
Yes, I may look into this. It is pretty tight under the generation meter, but I might be able to make some space!If you can get access to the cable (either the positive or neutral lead) between the inverter and the fuse box you could fit an Owl power monitor - the Micro+ should be fine and is pretty cheap. This will tell you what you are generating any time of the day.
Very true.I note that someone said that 1500W isn't ideal, as most appliances are more than that (washing machines, dishwashers and kettles tend to be about 2,200W) which is true, but that is to look at the issue from the wrong side. If you have an appliance taking power, then view it as an opportunity to soak up all of the power you are generating. Use appliances one after the other and never two at the same time - at least that way you maximise your solar contribution.
It's very strange, the roof is part of a 5 house terrace and could easily fit a lot more panels. For some reason the landlord decided to just fit 5 banks (one for each house) of six panels with huge gaps in between. I would have thought it would have served him better to fill the roof and increase his FIT payments, but I'm sure he has his reasons.May as well assume the panels are at a minimum 250w each, so the 6 would total a 1.5kW system. (However, with only space for 6, the landlord may have opted for higher-rated ones - I believe 327W panels are available).
May be worth simply asking the landlord what he had installed.
I think I may ask him what he had installed, but I may just get a blank stare. I'm not sure if he will be aware of the technicalities of it all.
Yes, I'm going to put together an RS232 cable next week and connect it up to my laptop.Once you get a cable hooked up to the inverter (for a start, anyway...), you may be able to pull out peak generation statistics, which would give a reasonable idea as to the actual system size.
Thanks for the great info so far!0 -
We are what I would call 'low users'.
I started taking import meter readings two weeks ago, and since then we have averaged 3.2kWh/day. I would love to know how much our generation has influenced that figure though, we had some cracking weather over that period!0 -
I note that someone said that 1500W isn't ideal, as most appliances are more than that (washing machines, dishwashers and kettles tend to be about 2,200W) which is true,
I think people get 'hung up' on the maximum power rating of appliances.
Agreed the washing machine might have a rating of say 2.5kW(2.2kW for the heater) but the heater is only for a few minutes in a cycle that could last 90 mins.
For instance my washing machine has indeed a 2.2kW heater and a cycle can last 90mins. However the consumption for the full cycle is 0.4kWh or 0.6kWh. So the average consumption is around 200 watts for the pump/motor; and as said earlier the heater is only on for a few minutes in the cycle. So even a small solar system will cover much of the appliance's consumption.
Putting on two appliances(say dishwasher/washing machine) at the same time is not a big problem as the heater cycle can be timed to be at different times. i.e the heater for both appliances is normally in the first 20 minutes. So putting on an appliance 20 minutes after the other appliance means they are normally only consuming(jointly) around 400watts.
Another point covered earlier, concerns the cost of water for those on water meters. The cost of water/sewerage varies across UK but can be from around £2 a cubic metre(1,000 litres) to nearly £6 for the South West.
The average water consumption on a washing machine cycle can be between 50 and 80 litres. So taking a figure of £3 a cubic metre, the water cost of a cycle would be 15p to 24p.
It is a temptation to put on a washing machine when it is not full, simply to take advantage of 'free electricity' and save, say, 5p to 7p in electricity costs; but effectively pay more in extra water costs.0 -
We wash almost everything on the Synthetic 30 & Synthetic 40 cycles on our machine. I have measured the total usage for each and it is a shade over 500W for the 40 cycle and a shade under 500W for the 30 cycle. So our system should cope ok with that on a nice sunny day.I think people get 'hung up' on the maximum power rating of appliances.
Agreed the washing machine might have a rating of say 2.5kW(2.2kW for the heater) but the heater is only for a few minutes in a cycle that could last 90 mins.
For instance my washing machine has indeed a 2.2kW heater and a cycle can last 90mins. However the consumption for the full cycle is 0.4kWh or 0.6kWh. So the average consumption is around 200 watts for the pump/motor; and as said earlier the heater is only on for a few minutes in the cycle. So even a small solar system will cover much of the appliance's consumption.
Yeah we are metered now and it is a concern to me. We are in the south west and the prices do seem high to me.Another point covered earlier, concerns the cost of water for those on water meters. The cost of water/sewerage varies across UK but can be from around £2 a cubic metre(1,000 litres) to nearly £6 for the South West.
Ours is quoted as 42l for the cycles we use.The average water consumption on a washing machine cycle can be between 50 and 80 litres.
Yes, I have been having words with the OH about only doing full loads. It is hard for her though, we have a 5 year old and school clothes come home mucky almost every day! I did wonder if it might be cheaper to buy extra school clothes, but the school insist on their official uniform with embroidered logo on virtually everything! Which can only be purchased through select stores! The only thing we save on is skirts and trousers which we get from Tesco.It is a temptation to put on a washing machine when it is not full, simply to take advantage of 'free electricity' and save, say, 5p to 7p in electricity costs; but effectively pay more in extra water costs.
When I went to school my parents were allowed to buy tops without logos, so long as the colour was right, and that's what they did. Even when I got to secondary school I had a standard blazer with a patch sewn on, but now they wont allow that either!
Lol, feels good to unload about school uniform, sorry it's so off topic! :rotfl:0 -
I think I just about have the space:If you can get access to the cable (either the positive or neutral lead) between the inverter and the fuse box you could fit an Owl power monitor - the Micro+ should be fine and is pretty cheap. This will tell you what you are generating any time of the day.
Can I clamp on either side of the meter?
Are the Owl devices not inaccurate at low levels though, due to the clamp being used as the method of measurement?
I also read elsewhere that smoothing capacitors in the inverter will affect any clamp monitor.
If I had the choice I would go for an optical monitor (that reads the pulses from the gen meter LED), but I have only found the GEO SOLO PV and that is a little steep at £100+.
Are there any cheaper optical monitors on the market?0 -
Can I clamp on either side of the meter?
Yes, current should be the same in all 4 wires. I chopped a bit of plastic out of the conduit and hung the clamp outside.Are the Owl devices not inaccurate at low levels though, due to the clamp being used as the method of measurement?
Yes, mine is wildly optimistic below 200W but accurate above that. So, an indication of lower than 200W says "Too little to bother with" so perfectly useful in that application.I also read elsewhere that smoothing capacitors in the inverter will affect any clamp monitor.
The inverter effectively produces mains as a series of pulses, which could well upset a clip-on sensor, so it may well depend on the inverter and how 'clean' the output is. All I can do is refer you to my previous answer. I've just bought the Owl Micro+ for a different use and it reads 16W from a pump very well - and at £25, a bargain.4kWp, Panels: 16 Hyundai HIS250MG, Inverter: SMA Sunny Boy 4000TLLocation: Bedford, Roof: South East facing, 20 degree pitch20kWh Pylontech US5000 batteries, Lux AC inverter,Skoda Enyaq iV80, TADO Central Heating control0
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