Octopus … Is there method in this madness ?

[Martin of WickParticipant @martinofwick]

And tidal streams run for 18 to 20 hours of the day.  Solar for half that if you are lucky in the summer and SFA in winter,  with its peak generation at a time of day when not required (unless we all fit heat pumps and use then for AC in summer). Storage would help, but it all costs money and would push up electricity costs even more.

 

 

 

[SillyOldDufferModerator @sillyoldduffer]

Well, don’t expect renewable energy to behave in the same way as nuclear, gas, oil and coal!   Actually all sources of energy have pros and cons.  Nuclear is good, apart from cleaning up after decommissioning.  Coal power stations cannot respond quickly to rising and falling demand, and are polluting.  Oil provides better response but is more expensive.   Gas is excellent because turbines can be fired up and down very quickly. And since 1990, gas has been very cheap.   Unfortunately low cost of gas is not guaranteed in perpetuity, and some suppliers are politically unreliable.

Energy has always been provided by a basket of different methods, and the methods are changing.  In the UK Town Gas is long gone, and Coal is now miniscule.   Oil and natural gas are both problematic, unless the source is local.  We have to change.

Renewable energy is free in the sense that no-one has to be paid to extract and transport millions of tons of coal, oil or gas.  Fossil fuels require a lot expensive middlemen, services and infrastructure between consumer and source.  In contrast renewables are simpler, going straight to electricity, which can be fed into the grid.   Though connecting to the grid is expensive, renewable electricity is still cheaper than other sources.    And much less polluting than burning carbon.   Whilst many don’t believe in global warming, they are wrong.  Failing to understand a problem does not fix it.

The disadvantage of renewable energy is it comes and goes depending on the weather and the planet’s position – sunshine, wind, tides, rainfall etc.  Dirt cheap, but not necessarily available when needed.  Therefore, some form of storage is needed.  Nothing new in that:  Dinorwig exists because off-peak nuclear and coal power was used to pump water into a huge mountaintop reservoir, and  discharged to top up the grid later.   Though horribly inefficient it was cheaper to burn coal continually during the night and pump water than it was to crank large boilers up and down.

Many storage options.  Using excess electricity to electrolyse water into Hydrogen and Oxygen; making Ammonia or Sodium;  pumping water uphill; pressuring gas; heating cast-iron blocks; charging batteries etc.  Giant batteries need not be expensive.  Expensive Lithium is needed for cars because it has a high energy density, but lower density storage is OK in a fixed installation, where Sodium is good enough.  Sodium is dirt cheap, especially when made with surplus renewable electricity…

The high cost of fossil fuels makes negative prices unlikely, though it can and does happen.  Oil went negative in the US a few years ago because deliveries exceeded the available storage capacity,  making it necessary for those contracted to store it to pay someone to take it away!  How markets are organised is important, and it’s not right yet, nor is the technology fully developed, and nor is the infrastructure in place.

But, there is nothing in switching to renewables that’s beyond the wit of man, either technically or in the mechanisms used to buy and sell it.  It will be different though.

What Octopus are doing makes sense in the context of how they buy and sell energy.  They wish to attract new customers, and will almost certainly be offering variable rate tariffs (via Smart Meters) that encourage customers to consume electricity when it is available, by dropping the price.   Very similar to Economy 7, though more agile.  All suppliers are going that way, step by step, so as not to frighten the horses, or make a major expense.

One thing for sure – burning fossil fuels isn’t sustainable.   In only 30 years, oil and gas will run short.  Sadly prices skyrocket when demand permanently exceeds supply.  I’ll probably be dead before petrol become unaffordable but my children will have to find alternatives.   Coal, gas and oil did us proud in the past, but they are finite natural resources.  God isn’t making any more…

Dave

 

 

 

[noel shelley]

On noel shelley Said:

The whole wind/solar idea seemed great on paper to the uninitiated but is in reality an uncontrollable monster. I have observed several big wind turbine farms all idle during the hot sunny spell we have been having, at least you can feather the blades ! Tidal is at least largely predictable !  Noel.

The whole lot is fully controllable.  No doubt about that, so absolutely nothing to do with the technology!

Wind turbines can be turned off – not by feathering the blades but by turning the rotor away from the wind direction.  Feathering the blades is simply a means to maximise the power delivered, by the turbine, as they are designed to rotate at a set, controlled speed.  This can occur when the wind speed is too high for the safety of the structure.  All turbines turn away from the wind to avoid over-speeding.

It is different than constraint.  Constraint occurs simply where the grid cannot absorb the power, or the grid would not be able to absorb/deliver all the available instantaneous power (the grid cannot store electricity, it can only transmit it from source to user).

The grid sometimes cannot transmit the power because it was built as a radial system from fossil power stations and the less ‘robust’ parts are at the extremities.  Off-shore wind turbine power comes ashore where the transmission grid may not yet be reinforced – hence the off-shore generation must be constrained.

The contract to get that large investment (for the installation of large numbers of turbines required, the government, at the time, guaranteed that they would be paid compensation if the grid was not reinforced in time.  Clearly it has not been reinforced adequately by the National Grid and paying curtailment payments is far cheaper than the turbines never having been installed in the first place (they would still be burning dirty, expensive coal and gas instead of renewable energy from the wind).

The other end of the scale is when there is too much generation – either it is used or lost by turning off turbines or switching off solar generation.  Switching off solar panels is simple – one can easily flip your switch at home, to stop your installed solar panel generation.

It is at these times when any surplus is sold cheaply to anyone who can ‘turn up their wick’.  The generation system is such that at times the price becomes negative.

The problem is that the grid still relies on gas generators for a ‘black start’ if there were to be a power outage.  It’s called ‘spinning reserve’ – steam driven generators are still needed for this stand-by duty at the present time, so they have to be kept turning, even if making little generated power – hence there is always (yet awhile) a couple of Gigawatts of gas-fired generation.

The National Grid are working towards being able to restart the grid (after a black-out) by other means.  Black-outs are necessary when there is, for some reason, insufficient generation due to an unexpected failure within the whole grid.  It could be a local power outage (relatively easy to sort out) or might cascade into a major system shut-down.  The National Grid has statuary responsibility to maintain both voltage and frequency of the supply within tight limits.

The grid can easily turn off a generator if there is too much power, but not enough is another story!  Turning off any generator (they all have at least half hour contracts to honour) costs money.  We only hear about wind constraints as they have been in the news for years.

Hope that lot helps to explain some of the misapprehensions circulating.  I’m no expert on the subject and ‘‘contracts for difference’’are yet another set of ‘juggling balls’ for the system to cope with.

Let’s be clear, there is no madness, whatsoever, involved with Octopus Energy, so I still stand by my original post.  Just someone trying to make a mountain out of a molehill, IMO.

As for time-of-use pricing, that has been going on for decades.  E7 for domestic users and power agreements for industry (night time power was far cheaper because coal-fired generators could not easily reduce output while maintaining efficiency).

Power costs could include not only time of day/night rates but also reducing usage for up to two hours at a time with (I think) only one or two hours notice when requested by the grid.  I can’t remember exactly how much power I had to shut down at these maximum demand periods (2-5GW was likely) and we regularly used 10GW (or more) during the cheap night rate period compared to the day rate.

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