Solar ... In the news

zeupater

michaels wrote: »

MY point being that given I already have both an inverter and a big battery pack you would have thought it should be possible to do the other bits and pieces to make use of storage at a price that would make the whole thing work as there would be no need to duplicate the two most expensive components.

Hi

Understand, but you'd still need some kind of device similar to the SMA storage management unit mentioned, a replacement integrated pv/storage management inverter or a more sophisticated inverter system with similar functionality built into the EV .... the cheapest currently available option would almost certainly be just to address the domestic storage management gap because you have two of the three main elements already ...

HTH
Z

zeupater

zeupater wrote: »

Hi

Understand, but you'd still need some kind of device similar to the SMA storage management unit mentioned, a replacement integrated pv/storage management inverter or a more sophisticated inverter system with similar functionality built into the EV .... the cheapest currently available option would almost certainly be just to address the domestic storage management gap because you have two of the three main elements already ...

HTH
Z

.... further to the above, here's Nissan's solution ideas on their Power Control System (PCS) ... http://www.nissan-global.com/EN/TECHNOLOGY/OVERVIEW/vehicle_to_home.html ... which would effectively perform the same role as the SMA unit, but just be tuned for their EV connectivity, battery pack etc ....

HTH
Z

michaels

zeupater wrote: »

.... further to the above, here's Nissan's solution ideas on their Power Control System (PCS) ... http://www.nissan-global.com/EN/TECHNOLOGY/OVERVIEW/vehicle_to_home.html ... which would effectively perform the same role as the SMA unit, but just be tuned for their EV connectivity, battery pack etc ....

HTH
Z

That's the set-up and as it mentions, the Leaf already takes a direct DC connection. The problem with dual tasking the PV inverter though is that at times you will want to charge the car via mains AC rather than just the PV DC and then feeding it back through the PV inverter means it also goes through the FIT meter.....

zeupater

michaels wrote: »

That's the set-up and as it mentions, the Leaf already takes a direct DC connection. The problem with dual tasking the PV inverter though is that at times you will want to charge the car via mains AC rather than just the PV DC and then feeding it back through the PV inverter means it also goes through the FIT meter.....

Hi

I don't believe that's what the PCS is doing in Nissan's own diagram or explanation .... it looks to be a unit matched to the Leaf battery which is connected directly to the distribution board. It needs to monitor domestic consumption and, very importantly, vary the AC output to match that load from a constant voltage source, the EV's battery pack. Your current pv inverter takes whatever is available on the DC side, matches existing grid conditions and converts it directly to AC up to the maximum allowed by the inverter's design without reference to what your house load is ... if you have a 4kW inverter and could even bodge everything together to feed from the EV, you'd be pulling 4kW until either the Leaf's cut-off threshold (if there is one) is reached or the battery is completely flat .....

Your best option is to talk directly to Nissan before you go any further ....

HTH
Z

Martyn1981

Article on storage in the UK. Sounds very optimistic for this decade.

I particularly noted the OCD pleasing estimate of annual deployment, which goes from 1(00MW) in 2016, and pretty much doubles every year through 2, 4, 8 to 16 (1,700MW) by 2020.

The mind boggles at what our leccy generation and storage will look like by 2030.

The Market & Opportunity For Energy Storage In The UK

Mart.

cells

batteries if they are to become a large scale feature are more useful on the solar farm side. They allow inverters and the grid connection to be utilized at a higher percentage. You could have a situation where a solar farm can be upgraded to about twice its current capacity without needing additional grid connections or inverter capacity.

right now they are a waste, charging and discharging introduces losses when your next door neighbors could be utilizing it at close to zero loss in fact it may be even worse than that the neighbor will be drawing upto 15% loss from the central grid. for all intents and purposes even if you are charging with solar and you have a grid connection you can view the process as charging and discharging from the grid with something in the order of 20% loss for the full cycle.

zeupater

cells wrote: »

batteries if they are to become a large scale feature are more useful on the solar farm side. They allow inverters and the grid connection to be utilized at a higher percentage. You could have a situation where a solar farm can be upgraded to about twice its current capacity without needing additional grid connections or inverter capacity.

right now they are a waste, charging and discharging introduces losses when your next door neighbors could be utilizing it at close to zero loss in fact it may be even worse than that the neighbor will be drawing upto 15% loss from the central grid. for all intents and purposes even if you are charging with solar and you have a grid connection you can view the process as charging and discharging from the grid with something in the order of 20% loss for the full cycle.

Hi cells

One of the main issues surrounding the argument against renewables technologies is that they are mainly intermittent by nature. We've heard all the arguments ... solar doesn't generate when grid demand is peaking ... wind doesn't blow all of the time ... tidal flow peaks don't match peak demand most of the time ... too much renewables generation will cause grid melt-down ... etc, so when a workable solution to most of the issues looks to have future viability, the storage round-trip efficiencies come into question ....

Leaving renewables aside, the round trip efficiency of many of the developing battery technologies isn't much out-of step with that of pumped storage, it's just that there's an issue with life-cycles at the moment. If the losses at Dinorwig are considered acceptable to soak-up excess overnight nuclear and renewables generation, why should other forms of storage be considered any different?.

A point to consider is that the energy industry is currently rolling out a hugely expensive project in the form of smart-metering with an aim to smooth peaks & troughs in demand. Leaving renewables technologies aside, an alternative and almost certainly more effective approach to achieving this objective would be through domestic scale storage, utilising cheap overnight supply to suppliment a peak-time demand shortfall ... all it needs at the moment is a level of demand to provide the volume related manufacturing economies-of-scale required to drive prices down to levels where both domestic-scale & utility-scale storage becomes financially viable ....

HTH
Z

cells

zeupater wrote: »

Hi cells

One of the main issues surrounding the argument against renewables technologies is that they are mainly intermittent by nature. We've heard all the arguments ... solar doesn't generate when grid demand is peaking ... wind doesn't blow all of the time ... tidal flow peaks don't match peak demand most of the time ... too much renewables generation will cause grid melt-down ... etc, so when a workable solution to most of the issues looks to have future viability, the storage round-trip efficiencies come into question ....

Leaving renewables aside, the round trip efficiency of many of the developing battery technologies isn't much out-of step with that of pumped storage, it's just that there's an issue with life-cycles at the moment. If the losses at Dinorwig are considered acceptable to soak-up excess overnight nuclear and renewables generation, why should other forms of storage be considered any different?.

A point to consider is that the energy industry is currently rolling out a hugely expensive project in the form of smart-metering with an aim to smooth peaks & troughs in demand. Leaving renewables technologies aside, an alternative and almost certainly more effective approach to achieving this objective would be through domestic scale storage, utilising cheap overnight supply to suppliment a peak-time demand shortfall ... all it needs at the moment is a level of demand to provide the volume related manufacturing economies-of-scale required to drive prices down to levels where both domestic-scale & utility-scale storage becomes financially viable ....

HTH
Z

dinorwig was a mistake and if it had not been built, it would not be built today

dinorwig does not store any significant quantity of energy on a national grid scale. Its more for power not for energy storage.

efficient lighting has already greatly smoothed the average and peak demands and this will continue for a time making the uk profile more flat

high cycle life cheap price batteries would be useful for many applications but not all that needed or useful until solar or wind get to a much higher percentage of the grid. they may be more useful on the solar farm side to reduce the overall cost by allowing more panels to inverters and grid connection lines and infrastructure.

the green fans expect the world to change overnight and draw nice exponential graphs but time will teach and tell...

Martyn1981

cells wrote: »

dinorwig was a mistake and if it had not been built, it would not be built today

dinorwig does not store any significant quantity of energy on a national grid scale. Its more for power not for energy storage.

Dinorwig wasn't a mistake, it was built to support the nuclear rollout, as was the creation of E7. However, the 'too cheap to meter' nuclear failed to arrive and nuclear generation never quite reached the expected scale.

Dinorwig does store significant energy on a national scale. Just take a look at Gridwatch and you'll see the peak balancing role it plays. Look at the weekly graph, and the shape of the generation profile.

Also remember that Dinorwig can supply power/energy within seconds of a request from the NG.

Also remember that Dinorwig allows us to take economic advantage of France's overproduction of nuclear at these times of the year, when they are practically 'giving it away'.

cells wrote: »

efficient lighting has already greatly smoothed the average and peak demands and this will continue for a time making the uk profile more flat

Higher efficiency goods like lighting, fridge/freezer compressors and TV's don't smooth average demand, they reduce it. Smoothing, suggests it gets moved somewhere else.

cells wrote: »

high cycle life cheap price batteries would be useful for many applications but not all that needed or useful until solar or wind get to a much higher percentage of the grid. they may be more useful on the solar farm side to reduce the overall cost by allowing more panels to inverters and grid connection lines and infrastructure.

I doubt there would be any significant savings from panel to inverter numbers, however, storage for leccy stabilisation can improve the value of the leccy from intermittent renewables, as seen in the US (Ohio).

I agree that on a national scale, storage of PV leccy is not yet needed. However, if storage improves the economics of domestic (and commercial) PV, then we could see a situation where PV is installed when it otherwise wouldn't have been.

As an example, a friend of mine is considering a large 20kWp PV install with batteries. This will run his property and export within the 3.68kW limit.

To enable this to work, he'll need 160kWh of lead acid batts. Interestingly, he's the person who previously gave me advice on large domestic batts in the 3p to 4p range, prompting you to call me a liar, as this information countered your domestic batt claims.

His pricing on this batt system comes out at 3p/kWh, or 2.13p/kWh after scrappage (lead value).

cells wrote: »

the green fans expect the world to change overnight and draw nice exponential graphs but time will teach and tell...

Funnily enough, I'd suggest it's the exact opposite. Green fans want a start and more effort, but have been shocked at the speed of response and success.

I've always thought the problem lied with the anti-renewable, fossil fuel fans, who kept telling us that progress was not achievable and recite pessimistic nonsense even after the fact.

I recall your claims that coal pollution is not harmful, and that Chinese coal consumption would increase till 2030, despite their coal consumption having already reduced in 2014 and then again in 2015.

Mart.

Martyn1981

Interesting development/testing of domestic PV and storage in Tasmania.

People power: Tasmanian residents to store solar energy and sell it back to grid

There are more than 1.5m households in Australia with rooftop solar. And in a few months time, 40 Tasmanian homeswill be acting as mini power stations – not just producing energy for their own consumption and to export back into the grid, but actively trading and profiting from the power they generate.

Much has been written about rooftop solar and the impending boom in battery storage but the key ingredient to turning homes into mini-power stations is the software that links the hardware of these technologies. Now the Canberra-based startup Reposit Power is helping to change the way households and energy companies think about solar and storage.

The trial that is to start in Bruny Island, south of Hobart, will see the households equipped with rooftop solar, battery storage, and Reposit’s GridCredits software.

These test rollouts are particularly important in Australia, where two reports have now concluded that up to 33% of households might disconnect from the grid if there aren't changes to the way leccy is priced, as domestic PV keeps getting cheaper and cheaper.

The research is important because it is now accepted that about half of all electricity demand will one day come from rooftop solar and battery storage from households and businesses, or near the point of consumption. This is known as distributed energy, a different system to the centralised system that has ruled the grid for a century or more.

Mart.