Navitron Renewable Energy and Sustainability Forum

General Renewable Topics => General Discussion => Topic started by: dan_b on May 15, 2019, 11:01:39 AM



Title: Graphs of a good solar day .
Post by: dan_b on May 15, 2019, 11:01:39 AM
Yesterday was pretty damned good on the solar generation front, my second highest day ever, so here are some pretty pictures.

My generation curve is lumpy due to shading impact at various points of the day and as the West facing panels come into play in the afternoon, but my SolarEdge does the best it can.

It's interesting looking at my battery monitor graph for the day too - you can see my "run the dishwasher during the E7 period" electricity demand around 1am, where the import is being lessened by the maximum the PowerVault can push out (still had plenty of charge left when we went to bed).

Then you can see the battery starts taking charge around 6.45am as the solar wakes up.
At 7.10am someone uses the 3kW kettle (not me, I use my 1kW one to minimise import, which is the PowerVault export spike around 7.40am, but the rest of my family, not so much!)
Then after that, everyone leaves the house and the Powervault sucks up as much charge as it can - 800W is the charging limit on my system.  Happily, the rest of the solar generation is then grabbed hold of by my ImmerSUN up until just before noon when it's clearly heated up the hot water tank sufficiently.  So for the rest of the afternoon, we see occasional spikes of high grid export, with short periods of lower grid export as the ImmerSUN keeps the immersion ticking over topping up the hot water tank.  And also you can see the battery charging input tailing down as it reaches full charge by 6pm.

At 6pm, the family starts arriving home and stuff gets switched on, so the PowerVault starts discharging in response. TV, PS4, lights, computer, toaster, and microwave all kicking in throughout the evening.

All good fun I think.

(https://i.postimg.cc/zHj0DgW6/good-battery-day.jpg) (https://postimg.cc/zHj0DgW6)

(https://i.postimg.cc/jCbT5YP4/good-solar-day.jpg) (https://postimg.cc/jCbT5YP4)


Title: Re: Graphs of a good solar day .
Post by: Paulh_Boats on May 15, 2019, 01:09:46 PM
Dan,

Which device measures grid in/out power? It's quite fascinating to see the in/out flow during the day.

The cyan and blue lines were difficult to distinguish for me, but I got what was happening.

A cool feature would be knowing what each device consumed - then toasters, electric showers and tumble dryers would be abandoned en masse. ;D

Paul


Title: Re: Graphs of a good solar day .
Post by: dan_b on May 15, 2019, 01:26:49 PM
So the graph showing import/export is the PowerVault monitoring portal. It's rather clunky and with everything jammed together on the same axis is hard to work out what's going on sometimes.  I fed back to them about 2 years ago that import and export should be in different directions on the y-axis as that shows current flow more intuitively, but they seem stuck on this visual representation.

I guess if every device had its own IoT IP or MAC address you could determine what device was doing what at any particular time automatically, or perhaps "smart plugs", or if you put current clamps on the supply cables to every device in the home and connected them all up to a custom monitor (like a EnergyMon) you could probably do that, but you'd have to be totally obsessed! 



Title: Re: Graphs of a good solar day .
Post by: Iain on May 15, 2019, 01:46:09 PM
Hi Dan
Very similar
I see your Powervault charges at 800W (is that lead acid?)


Iain


Title: Re: Graphs of a good solar day .
Post by: Paulh_Boats on May 15, 2019, 02:20:10 PM
Good pioneering work chaps.

However I have always been skeptical of domestic battery storage. The only exception is no grid connection.

With 10% to 20% heating losses, battery degradation and replacement the costs are high.

Better to have a smart National Grid, dynamic load balancing and steady reduction in national consumption in line with 2050 targets.

New systems should get paid 100% for exported kWh, then you don't need domestic storage. Simples!

If there is too much renewables we could charge up the Dinorwig pumped storage, roughly 2GW.

Paul


Title: Re: Graphs of a good solar day .
Post by: dan_b on May 15, 2019, 02:58:34 PM
Yeah, mine is a 4KW lead acid model - I was a very early adopter -  so it charges at a max of 800W but can discharge at a maximum of 1100W.  It seems low (certainly compared to the Powerwall!), but it does mean that on a good day like this there's enough surplus to be able to heat the ImmerSUN as well as charge the battery.

Hi Dan
Very similar
I see your Powervault charges at 800W (is that lead acid?)


Iain


Title: Re: Graphs of a good solar day .
Post by: pantsmachine on May 15, 2019, 03:41:57 PM
Looks good Dan, epic time to have no meters turning while NG and govt think about how to not implement renewables further. :)


Title: Re: Graphs of a good solar day .
Post by: dan_b on May 18, 2019, 01:39:24 PM
Ha yes indeed. Crazy isn't it. Especially when you consider how much progress the UK actually has made in offshore wind in particular. banghead:


Title: Re: Graphs of a good solar day .
Post by: dimengineer on May 22, 2019, 04:05:07 PM
Dan,

Which device measures grid in/out power? It's quite fascinating to see the in/out flow during the day.

The cyan and blue lines were difficult to distinguish for me, but I got what was happening.

A cool feature would be knowing what each device consumed - then toasters, electric showers and tumble dryers would be abandoned en masse. ;D

Paul

I'm going to disagree with yur last sentence a bit. The numbers might make people think, and educate them some, but I don't believe for one second that the'y abandon showers, or toast. What other ways of getting hot water are there? Of making toast? I agree with Tumble dryers. Devils spawn. Whats wrong with old fashoined clothes lines?


Title: Re: Graphs of a good solar day .
Post by: Paulh_Boats on May 22, 2019, 04:36:16 PM
Dan,

Toast and marmalade - yum yum  8)

Make your own bread (with electric while the sun shines) and the loaves come out hot. It's not crunchy, but warm homemade bread is really nice.

Navitron have a great range of solar thermal panels - our 30 tubes give free hot water April to October. Sunny winter days will make the water warm enough for a shower. Our electric shower was toast (ha ha) soon after the solar thermal panel was plumbed in.  I replaced it with a gravity shower and pump, saving 8.5kW.

My grandmother had twin washing lines! We raised 3 daughters and have never owned a tumble drier and never will.

We had it rough. Baths in the kitchen sink, mum and gran said they slept in the Anderson shelter when the bombs dropped.

Paul

PS All true.  ;D


Title: Re: Graphs of a good solar day .
Post by: dimengineer on May 22, 2019, 09:56:58 PM
Dan,

Toast and marmalade - yum yum  8)

Make your own bread (with electric while the sun shines) and the loaves come out hot. It's not crunchy, but warm homemade bread is really nice.

Navitron have a great range of solar thermal panels - our 30 tubes give free hot water April to October. Sunny winter days will make the water warm enough for a shower. Our electric shower was toast (ha ha) soon after the solar thermal panel was plumbed in.  I replaced it with a gravity shower and pump, saving 8.5kW.

My grandmother had twin washing lines! We raised 3 daughters and have never owned a tumble drier and never will.

We had it rough. Baths in the kitchen sink, mum and gran said they slept in the Anderson shelter when the bombs dropped.

Paul

PS All true.  ;D

Do you not shower October to April?  :)


Title: Re: Graphs of a good solar day .
Post by: Paulh_Boats on May 22, 2019, 10:37:13 PM
Ha ha, we run around outside when it rains and snows.  :laugh:

I begrudgingly turn on the gas boiler for an hour, if the water is cool in the winter. The thermostat is cranked down to 45C which is warm enough for showers.

Even on a cloudy day the water can get half way, like 30C which saves some gas.

We are convinced a solar thermal panel + PV panels should be on every house. A hot water cylinder is a convenient and cheap battery - storing today's heat for a cloudy tomorrow.

Paul


Title: Re: Graphs of a good solar day .
Post by: langstroth3 on June 10, 2019, 03:19:27 PM
So the graph showing import/export is the PowerVault monitoring portal. It's rather clunky and with everything jammed together on the same axis is hard to work out what's going on sometimes.  I fed back to them about 2 years ago that import and export should be in different directions on the y-axis as that shows current flow more intuitively, but they seem stuck on this visual representation.

I guess if every device had its own IoT IP or MAC address you could determine what device was doing what at any particular time automatically, or perhaps "smart plugs", or if you put current clamps on the supply cables to every device in the home and connected them all up to a custom monitor (like a EnergyMon) you could probably do that, but you'd have to be totally obsessed! 



Sounds like you've been using PowerVault for a while. Pleased with the savings? I'm thinking of getting one myself (4kw array on roof), so just curious.
Any thoughts on the GridFlex aspect that the likes of EDF offer?