Solar ... In the news

QrizB

JKenH said:

An ideal situation for smart charging perhaps tailored to the output from the panels with the opportunity for the driver to elect to pay for any electricity at a higher rate when insufficient solar was available (a bit like the options available on a Zappi charger: a) pure solar or nothing, b) a constant charge at minimum 1.4kw increasing when the sun comes out, or c) a full 6.6kw charge.

Yes, I was thinking of something along those lines. Discounted charging when the sun shines and market-rate when it doesn't.

zeupater

2nd_time_buyer said:

Yes, interesting point about how many nuclear reactors. On one hand solar generates during the day, so I guess 1gwh of day time energy is more useful than 1gwh of night time energy. Perhaps winter GWh might be more valuable than summer, tipping favour towards wind. Increasingly , you might expect "guaranteed" energy such as FF and nuclear to command a higher value than flighty renewables. I am not sure where I am going with this, other we might be moving into territory where all GWh are not born equal.

Hi

This is effectively the very point that many (including me!) have been harping on about & been boring everyone over for years ....

Knowing that generation will be available to a defined schedule is not something which would be nice in a low carbon society ... it's the paramount consideration when looking at the required mix.

If that reality is to be met though gas generation then the consequences of not meeting emissions targets need to be accepted ... if the answer is centralised nuclear then there's the massive lead times & long term costs to consider ... if it's nuclear via SMRs then someone needs to make a decision to build a production line & designate appropriate sites pretty soon ... but then again, a combination of tidal flow & matched storage (battery, tidal lagoon, pumped storage) sized  to cover slack tidal flow times can provide a modular & fully scaleable solution which should be possible to start rolling out within relatively tight timescales which can be aligned to decarbonisation of generation elsewhere ....

Okay, whichever solution is preferred it'd be expensive & take time, so it simply comes down to lead time & financing, so here's a fully logical proposal that'll definitely trigger some, but as all options will have their decriers, it's simply a case of needing to push ahead and start generating, which likely means that a scaleable approach is needed, which effectively discounts centralised nuclear plant.

So, instead of concentrating on technology, what would a strategic pathway look like .... well, how about looking at reducing imports of shipped LNG and start taking the resulting savings (large reductions in embedded emissions & necessary investment in ships etc) on board as soon as possible ... of course, this would be achieved by relocating fracked gas supply sources from the middle east, USA etc ... but what's the issue with that considering the ultimate benefits? ... 

What exactly are the Benefits? ... LNG production & delivery is highly energy intensive & therefore both relatively expensive & more emissions intensive than local sources of natural gas and whatever is imported needs to be paid for, effectively supplementing the economies & tax-take elsewhere ... something which could be converted into UK carbon reductions & increased taxable economic activity here in the UK, providing a solution to both energy independence & funding of the long-term generating solution ... yes the argument is that gas should stay in the ground, but that's not what everyone is voting for everyday by continuing to use gas for heating/cooking and any electricity that's been generated by gas. If there was a political will (ultimately driven by voters & economic activity) to ring-fence the appropriate additional tax-take & invest that directly into weaning the economy off the fracked gas as scaleable replacement generation comes on line, then we've described a logical self-sustaining affordable pathway to meeting emission reduction targets without destroying either the economy or the climate ....

... then again, there's always the little 'fishies' & 'birdies' as well as imperceptibly low earth tremors to enable some to convince us all to worry about ... but isn't it about time for us all to appreciate that everything has risks and actually doing & achieving something is better for everything than doing nothing? ... 

HTH - Z     

michaels

zeupater said:

2nd_time_buyer said:

Yes, interesting point about how many nuclear reactors. On one hand solar generates during the day, so I guess 1gwh of day time energy is more useful than 1gwh of night time energy. Perhaps winter GWh might be more valuable than summer, tipping favour towards wind. Increasingly , you might expect "guaranteed" energy such as FF and nuclear to command a higher value than flighty renewables. I am not sure where I am going with this, other we might be moving into territory where all GWh are not born equal.

Hi

This is effectively the very point that many (including me!) have been harping on about & been boring everyone over for years ....

Knowing that generation will be available to a defined schedule is not something which would be nice in a low carbon society ... it's the paramount consideration when looking at the required mix.

If that reality is to be met though gas generation then the consequences of not meeting emissions targets need to be accepted ... if the answer is centralised nuclear then there's the massive lead times & long term costs to consider ... if it's nuclear via SMRs then someone needs to make a decision to build a production line & designate appropriate sites pretty soon ... but then again, a combination of tidal flow & matched storage (battery, tidal lagoon, pumped storage) sized  to cover slack tidal flow times can provide a modular & fully scaleable solution which should be possible to start rolling out within relatively tight timescales which can be aligned to decarbonisation of generation elsewhere ....

Okay, whichever solution is preferred it'd be expensive & take time, so it simply comes down to lead time & financing, so here's a fully logical proposal that'll definitely trigger some, but as all options will have their decriers, it's simply a case of needing to push ahead and start generating, which likely means that a scaleable approach is needed, which effectively discounts centralised nuclear plant.

So, instead of concentrating on technology, what would a strategic pathway look like .... well, how about looking at reducing imports of shipped LNG and start taking the resulting savings (large reductions in embedded emissions & necessary investment in ships etc) on board as soon as possible ... of course, this would be achieved by relocating fracked gas supply sources from the middle east, USA etc ... but what's the issue with that considering the ultimate benefits? ... 

What exactly are the Benefits? ... LNG production & delivery is highly energy intensive & therefore both relatively expensive & more emissions intensive than local sources of natural gas and whatever is imported needs to be paid for, effectively supplementing the economies & tax-take elsewhere ... something which could be converted into UK carbon reductions & increased taxable economic activity here in the UK, providing a solution to both energy independence & funding of the long-term generating solution ... yes the argument is that gas should stay in the ground, but that's not what everyone is voting for everyday by continuing to use gas for heating/cooking and any electricity that's been generated by gas. If there was a political will (ultimately driven by voters & economic activity) to ring-fence the appropriate additional tax-take & invest that directly into weaning the economy off the fracked gas as scaleable replacement generation comes on line, then we've described a logical self-sustaining affordable pathway to meeting emission reduction targets without destroying either the economy or the climate ....

... then again, there's always the little 'fishies' & 'birdies' as well as imperceptibly low earth tremors to enable some to convince us all to worry about ... but isn't it about time for us all to appreciate that everything has risks and actually doing & achieving something is better for everything than doing nothing? ... 

HTH - Z     

Isn't there a problem with tidal being finite?

Surely storage of renewables through H2 or other long term mediums (or even using renewable spill to power CO2 sequestration of the emissions from FF used during renewable energy droughts) is the likely long term solution?

2nd_time_buyer

My guess is that by the end of the decade the problem of continuity of supply will begin to sort itself. But it will only happen once the value of it increases. Be it from interconnects from Iceland to Morocco, sodium/lithium batteries, time of use tariffs, or through over supply of renewables or a combination of all the above and more. In the mean time we will muddle through with the dwindling supplies of North sea gas and the government will procrastinate on nuclear.

zeupater

michaels said:

zeupater said:

2nd_time_buyer said:

Yes, interesting point about how many nuclear reactors. On one hand solar generates during the day, so I guess 1gwh of day time energy is more useful than 1gwh of night time energy. Perhaps winter GWh might be more valuable than summer, tipping favour towards wind. Increasingly , you might expect "guaranteed" energy such as FF and nuclear to command a higher value than flighty renewables. I am not sure where I am going with this, other we might be moving into territory where all GWh are not born equal.

Hi

This is effectively the very point that many (including me!) have been harping on about & been boring everyone over for years ....

Knowing that generation will be available to a defined schedule is not something which would be nice in a low carbon society ... it's the paramount consideration when looking at the required mix.

If that reality is to be met though gas generation then the consequences of not meeting emissions targets need to be accepted ... if the answer is centralised nuclear then there's the massive lead times & long term costs to consider ... if it's nuclear via SMRs then someone needs to make a decision to build a production line & designate appropriate sites pretty soon ... but then again, a combination of tidal flow & matched storage (battery, tidal lagoon, pumped storage) sized  to cover slack tidal flow times can provide a modular & fully scaleable solution which should be possible to start rolling out within relatively tight timescales which can be aligned to decarbonisation of generation elsewhere ....

Okay, whichever solution is preferred it'd be expensive & take time, so it simply comes down to lead time & financing, so here's a fully logical proposal that'll definitely trigger some, but as all options will have their decriers, it's simply a case of needing to push ahead and start generating, which likely means that a scaleable approach is needed, which effectively discounts centralised nuclear plant.

So, instead of concentrating on technology, what would a strategic pathway look like .... well, how about looking at reducing imports of shipped LNG and start taking the resulting savings (large reductions in embedded emissions & necessary investment in ships etc) on board as soon as possible ... of course, this would be achieved by relocating fracked gas supply sources from the middle east, USA etc ... but what's the issue with that considering the ultimate benefits? ... 

What exactly are the Benefits? ... LNG production & delivery is highly energy intensive & therefore both relatively expensive & more emissions intensive than local sources of natural gas and whatever is imported needs to be paid for, effectively supplementing the economies & tax-take elsewhere ... something which could be converted into UK carbon reductions & increased taxable economic activity here in the UK, providing a solution to both energy independence & funding of the long-term generating solution ... yes the argument is that gas should stay in the ground, but that's not what everyone is voting for everyday by continuing to use gas for heating/cooking and any electricity that's been generated by gas. If there was a political will (ultimately driven by voters & economic activity) to ring-fence the appropriate additional tax-take & invest that directly into weaning the economy off the fracked gas as scaleable replacement generation comes on line, then we've described a logical self-sustaining affordable pathway to meeting emission reduction targets without destroying either the economy or the climate ....

... then again, there's always the little 'fishies' & 'birdies' as well as imperceptibly low earth tremors to enable some to convince us all to worry about ... but isn't it about time for us all to appreciate that everything has risks and actually doing & achieving something is better for everything than doing nothing? ... 

HTH - Z     

Isn't there a problem with tidal being finite?

Surely storage of renewables through H2 or other long term mediums (or even using renewable spill to power CO2 sequestration of the emissions from FF used during renewable energy droughts) is the likely long term solution?

Hi

For years I've been reading that there's a 'limit' of ~10GW in UK waters or there's enough to supply ~11% of UK energy demand, but when it comes down to it neither figures make much sense when even a basic level of logic is applied ....

Think about it this way ... if water is over 800x the density of air then a suitably engineered array of tidal flow turbines having a basic swept area equivalent to a wind farm would theoretically produce ~800x more power for any given flow speed, moreover, the increased density results in a far lower flow rate to start generation. Additionally, the increased density of water is heavily influenced by gravity (V) and the mass of both 'surrounding' and 'pushing' flow (H) when compared to that of air, therefore the impact of turbulence is heavily impaired, opening the ability to farm the energy multiple times over a much shorter distance than with wind ....

Just as with wind turbines, as flow speed doubles the power generation potential increases x8, effectively this can be engineered to leverage a ~8x multiplication effect by simply constricting the cross sectional area of flow by ~50% through a form of funnel, a little like a tidal race would naturally accelerate flow rate to a point where even a relatively slow velocity overall tidal flow can become extremely energy dense in certain places ...    

The untapped potential is huge ... the Severn estuary alone has a tidal range of ~5m-15m, so if the average was taken at 10m, that's up to 100,000 tonnes of water per hectare of surface area moving both ways twice a day, so ~400,000 tonnes of mass flowing at a velocity of up to 1.5m/s (5.4km/h) ... just constricting the flow to double the velocity in a scheme contained within just 1 hectare of seabed would have provided a pretty good place to have started a fully schedulable renewable energy research project 50years ago .... however, as it wasn't done, the age old question remains 'cui bono?'

HTH - Z   

michaels

Alternatively: tide0.pdf (stanford.edu)

The logic depends on an assumption that we will use 2% more energy every year which over a 'relatively' short period becomes an extremely large number.

zeupater

michaels said:

Alternatively: tide0.pdf (stanford.edu)

The logic depends on an assumption that we will use 2% more energy every year which over a 'relatively' short period becomes an extremely large number.

Hi

... so the question effectively comes down to where does the energy come from and if the energy isn't collected where does it inevitably go and what does it do .... may I suggest that the moon, the seabed and shoreline may have some influence and that tidal energy isn't as much a closed loop system as it may at first seem ... next thing they'll be saying is that if we harvest the tides the moon will come crashing down on our heads as the gravitation attraction will become stronger if the tidal range isn't as fluid for some reason ... seeing that the moon's been moving away at ~1.5"/year for longer than life on earth has been around and the rotation of the earth has been slowing by ~2milliseconds per century for a similar length of time, likely linked to existing tidal friction, I doubt the fractional effect of tidal flow harvesting will have enough differential impact to even be measured before the expanding sun boils off all of the the seawater anyway ... better put the shades on then ...

HTH - Z

michaels

zeupater said:

michaels said:

Alternatively: tide0.pdf (stanford.edu)

The logic depends on an assumption that we will use 2% more energy every year which over a 'relatively' short period becomes an extremely large number.

Hi

... so the question effectively comes down to where does the energy come from and if the energy isn't collected where does it inevitably go and what does it do .... may I suggest that the moon, the seabed and shoreline may have some influence and that tidal energy isn't as much a closed loop system as it may at first seem ... next thing they'll be saying is that if we harvest the tides the moon will come crashing down on our heads as the gravitation attraction will become stronger if the tidal range isn't as fluid for some reason ... seeing that the moon's been moving away at ~1.5"/year for longer than life on earth has been around and the rotation of the earth has been slowing by ~2milliseconds per century for a similar length of time, likely linked to existing tidal friction, I doubt the fractional effect of tidal flow harvesting will have enough differential impact to even be measured before the expanding sun boils off all of the the seawater anyway ... better put the shades on then ...

HTH - Z

I think the maths works, meeting current demand the extra energy extracted is 9 orders of magnitude too low to be a problem but if you increase the energy demand by 2% pa for 1000 years (1.02^1000) then you get a number 8 orders of magnitude larger....

Martyn1981

Is that 2% increase in energy based on curent net energy consumption? I'm assuming so, v's the primary energy in FF's, otherwise energy consumption will be falling (fast) not rising.

But, putting that aside, will our energy demand increase by 2%pa? In the UK we are increasing our leccy needs (or will soon), perhaps by 100-150% in the next two or three decades, but that won't be a net increase in energy, as we move from other sources. In fact the energy for space heating will fall significantly with HP's.

Add in the fact that few countries will be able to make significant use of tidal energy, the UK being one of the few, and perhaps we are only looking at 1%, with little to no annual increase?

Totally appreciate that the study is looking at a theoretical harm, based on too much energy extraction, so a great link. There may also be an economical point of maximum tidal energy use. As wind and solar get ever cheaper, once we've hit net zero (fingers crossed) across the World, then any and all energy increases from there on will most likely be in economical balance with wind and solar deployments.

Any news / reports on the potential for tidal energy around the World? I'm assuming (which is dangerous of course) that the UK's potential is somewhat exceptional?

michaels

Martyn1981 said:

Is that 2% increase in energy based on curent net energy consumption? I'm assuming so, v's the primary energy in FF's, otherwise energy consumption will be falling (fast) not rising.

But, putting that aside, will our energy demand increase by 2%pa? In the UK we are increasing our leccy needs (or will soon), perhaps by 100-150% in the next two or three decades, but that won't be a net increase in energy, as we move from other sources. In fact the energy for space heating will fall significantly with HP's.

Add in the fact that few countries will be able to make significant use of tidal energy, the UK being one of the few, and perhaps we are only looking at 1%, with little to no annual increase?

Totally appreciate that the study is looking at a theoretical harm, based on too much energy extraction, so a great link. There may also be an economical point of maximum tidal energy use. As wind and solar get ever cheaper, once we've hit net zero (fingers crossed) across the World, then any and all energy increases from there on will most likely be in economical balance with wind and solar deployments.

Any news / reports on the potential for tidal energy around the World? I'm assuming (which is dangerous of course) that the UK's potential is somewhat exceptional?

I suspect it is entirely spurious, any calculation that assumes we will need 8 orders of magnitude more energy in 1000 years time is likely to show this is impossible regardless of source....(eg wind turbines, solar panels, nuke plants would probably need to cover the entire surface of the planet)