Random Renewables Thread

graememk

https://www.boards.ie/discussion/comment/121830550#Comment_121830550

I've done that on batteries/tractor etc. but creating and disconnecting the actual short? Or am I overthinking it a bit?

deezell

https://www.boards.ie/discussion/comment/121830674#Comment_121830674

So 12 panels say, 500V o/c and 11 amps available with full illumination, and they're asking you to short that? That >5kw capacity, but maybe higher instantaneous due to panel capacitance. That's a big bang in my book.

10-10-20

No issue shorting a panel, it has a high internal resistance so it drops the voltage massively and just sucks it up.

It's a psychological barrier though all the same... 500v DC... goes against intuition.

graememk

https://www.boards.ie/discussion/comment/121830810#Comment_121830810

That's what I sorta expected. But wasn't sure.

If you short out a bench power supply, the voltage goes to more or less 0. (To set a constant current)

1v at 11 amps is little power.

allinthehead

https://www.boards.ie/discussion/comment/121831266#Comment_121831266

The voltage in the panels will drop to zero too, I wouldn't leave them shorted for too long though.

Some nice test gear out there now.

https://youtu.be/yiuZkfuwzPs?si=ILCBtssOA-PVVRsf

SD_DRACULA

https://www.boards.ie/discussion/comment/121830674#Comment_121830674

There was a spark when we tested the DC current on newly installed 12 panels with a multimeter, prob 450v and max 10a, but also could have been a crap multimeter

10-10-20

https://www.boards.ie/discussion/comment/121831380#Comment_121831380

You'll get a spark as the 500v jumps between the contacts, then the V drops away rapidly and current picks up.

allinthehead

https://www.boards.ie/discussion/comment/121830087#Comment_121830087

A REC is a registered electrical contractor ie, registered with Safe Electric. A REC can be a QC but doesn't have to be, they can employ a QC. You can only be a QC for one company and I believe you must be a qualified electrician or electrical engineer to do a QC course. A company must have sufficient QC's to cover their workload.

DC999

Good newsletter from Ember | Clean Energy Policy | Clean energy policy and data (ember-climate.org) (sign-up is towards the end of the page). It looks at data around moving to cleaner+greener fuels. Has a lot of EU info and infographics so easy to digest, and can deepdive if you want more. Load of good info on the site too, and they summarise a lot of the recent stuff in the monthly newsletter.

Here's the link to this months one: Ember Monthly Insights - Global Electricity Transition (ember-climate.org)

For someone who worries about this stuff, there are some positive trends of what's already in place and what is planned renewable wise.

Fantana2

Anyone heard any status update on the green loans backed by the Government for house upgrades? Thought I read it was to go live in Feb but have seen nothing recently.

deezell

https://www.boards.ie/discussion/comment/121837164#Comment_121837164

My read on all this is that as fast as we adopt means of supplying our own energy, the utilities are skewing the price of grid energy to make up, such that off peak energy is almost as expensive as peak used to be, despite wholesale prices under 10c. Every effort people make to save is gobbled up by stealth, in all areas of life. You can't win.

unkel

https://www.boards.ie/discussion/comment/121841257#Comment_121841257

Ah you can win. Make the effort to save by investing in a decent setup. I have done and all I now ever pay for electricity is 5c / kWh. And all the electricity I produce, I can sell to the grid for 25c / kWh

Total electricity bill for the year (including 2 EVs) is negative

And beside the financials, my setup makes a significant contribution to the transition to clean energy by stablisising the grid (as well as my large PV setup and zero emissions motoring)

deezell

https://www.boards.ie/discussion/comment/121841282#Comment_121841282

How large is large. 30+ panels?

deezell

It's just that to go negative for the average household with two cars and a modest 15000km/car/annum, requires a system capable of 3000kwh each for the cars, and 4000kwh per annum for the home. Thats 10,000kwh/annum., which requires a kw of panels per 750kwh/annum, or 13.33kw in total. That 30 panels at least. How many 2 car homes can fit 30 panels? The high density new builds near me have 3 or 4 at most, with the odd detached house with 6. It's nonsensical to suppose that its possible to have negative annual usage of grid power for the vast bulk of people, and that's before you add in mandatory heatpump power guzzlers in some schemes. Most of this grid power is generated with 80% fossil fuels, so evs and heatpumps are in no way zero emitters.

Victor

"Most of this grid power is generated with 80% fossil fuels" - its about 60% over the space of a year.

deezell

There's little sun when those heatpumps are humming, its dark. I'd take those figures with a pinch of salt. Heatpumps are running from 80% fossil at least, losing 70% of the gas heat as waste to generate electricity, instead of burning it with 97% efficiency directly in the home. You can't dress that up no matter how you try. Social and affordable home families can't afford their bloated hearpump electricity bills, and are using super sers and bottled gas to heat one or two rooms.

unkel

https://www.boards.ie/discussion/comment/121841523#Comment_121841523

Nope to go negative you don't even need to produce any PV. But yes I do have well over 30 panels. Yet I live in a small starter 3-bed semi-D home in one of the cheaper Dublin suburbs

And your figures are wrong. During night rate hours, the grid is already well over 50% renewable on average. Sometimes up to 75% (even during the day) and these percentages are increasing every year

idc

https://www.boards.ie/discussion/comment/121841523#Comment_121841523

Even still it would better if the new estates used the full extent of roof available for panels as it seems they all put in a minimum number of panels I guess to achieve some building code/BER level and it usually seems based on size of the house. New estate near me varies from 4-7 panels. Often you'll see 5 or 7 where they could of easily fit one more to at least be symmetrical and worse in most of these houses they could easily fit double the number panels! Or even put panels on both sides of an East/West roof.

unkel

https://www.boards.ie/discussion/comment/121847668#Comment_121847668

In the Netherlands there is now a new word for it: "shame panels"

Such a waste of an opportunity, the people who have signed off on having just a few panels on new homes should be ashamed of themselves...

allinthehead

https://www.boards.ie/discussion/comment/121850647#Comment_121850647

I reckon half of them don't even work.

Scoopsire

Saw this from Australia, dynamic export limitation, can't imagine we'll see it here any time soon based on how long it took for the FIT.

"The previous fixed export limit of 5 kW per phase has been effectively doubled in Victoria. New compliant inverters can now export between 1.5 kW and 10 kW per phase, likely to operate at the upper limit most of the time. For comparison, ARENA’s South Australian “Flexible Exports For Solar PV Final Trial Report“, which ran from September 2021 to March 2023, reported a higher result than expected:

“The statistical spread based on data collected in the trial shows that, on average, devices were able to export at 10kW or their inverter capacity for 99.4% of the time, far exceeding the 98% target.”

For states that have implemented dynamic exports, this means more electricity is exported to the grid on average annually, resulting in more feed-in tariffs offsetting customers’ bills and more money in their pockets. Alternatively, the lack of dynamic export functionality within the grid might require DNSPs to restrict the installation of additional rooftop solar PV systems, limiting the solar industry’s growth."

https://www.solarquotes.com.au/blog/dynamic-solar-exports-victoria/

10-10-20

https://www.boards.ie/discussion/comment/121851054#Comment_121851054

Mandate batteries with all solar on the basis of a ratio of kWh storage to kWp solar and do away with solar-only connections? In Australia that battery ratio would be a lot higher than here in Ireland. Have a look at the DEPT thread on here too.

https://www.boards.ie/discussion/2058336271/dynamic-electricity-price-tariffs-consultation-paper

unkel

https://www.boards.ie/discussion/comment/121852092#Comment_121852092

No need for any mandatory batteries. Just let us have variable rates. This is extremely profitable for people with powerful inverters and large batteries. Market forces will nudge people to voluntarily invest in these systems and they will be well rewarded for it

10-10-20

https://www.boards.ie/discussion/comment/121852243#Comment_121852243

I'm referring to Australia - land of sunshine, where the grid could get overloaded with excess solar. 😁 Can't see that happening here, evah.

unkel

https://www.boards.ie/discussion/comment/121852314#Comment_121852314

Well you're gonna be surprised, but you got that wrong, it will happen here. The Netherlands have similar solar irradiation as Ireland, if anything, a bit worse than here.

Yet any time the sun shines during the mid day hours, the price of electricity goes negative because of the huge solar PV installed. There is now more PV per capita in the Netherlands than in sunny Australia.

We need an awful lot more PV here. Ireland as always is a good 5-10 years behind, but catching up. I spent a good 3 hours on public transport yesterday around Dublin and the east coast down to Wexford with nothing better to do than look out the windows and to my surprise there was quite a bit more PV already than I expected. And not just in Dublin

slave1

On routes I have not travelled on in a few months I've noticed new arrays, thing is I can pass a house this morning on the way to work and by the time I pass again on the way home all the panels can be up, it's lightening quick

I was first in my estate and row of houses, next door followed within a few months, then lots of queries from neighbours passing etc, now there are two more on the row of 11. 4/11 is great to see

the_amazing_raisin

Has anyone ever looked at getting the 20kVA single phase connection?

I'm thinking if going for a larger system and NC7, then it might be worthwhile paying the extra to upgrade to 16kVA from 12kVA to take advantage of extra export capacity

Then there's also the 20kVA connection for about €1,200 more plus MV network charges

I'm guessing that ESBN would run a new cable from the local MV transformer to the mini pillar and then to my house?

The charges include trenching costs which would immediately make it way too expensive (it's already on the very edge of ever paying for itself)

But if they just use existing ducting then do those charges apply?

graememk

https://www.boards.ie/discussion/comment/121948906#Comment_121948906

@mp3guy I think you've went for the 29kVA upgrade didnt you?

unkel

https://www.boards.ie/discussion/comment/121948906#Comment_121948906

Did you look up what the standard fee is for the upgrade? Even the modest upgrade from 12kVA to 16kVA where the ESB doesn't have to do anything except flip a switch on a computer, costs an eye watering €2068. I guess those mega salaries / pension packages have to be paid somehow...

the_amazing_raisin

https://www.boards.ie/discussion/comment/121949097#Comment_121949097

Covers the diesel costs of sending someone out to check you've the correct size fuse 😏

Had a similar experience with the night meter, despite it being only a paper exercise they still needed to send someone out

That's kind of my thinking about the 20kVA, more capacity per euro spent if the network charges aren't that big