The future of energy generation and storage

[Smurf1976]

Feed in grid connected private generators have contributed to the cost of grid generation capacity through their own investment in it. The broad question is the return these private generators should be entitled to for their investment balanced against the cost of maintaining the grid.

There's 4 basic cost components of electricity supply.

1 - Cost of having the grid run to each location that requires it.
2 - Cost of capacity on that same grid.
3 - Cost of peak generating capacity.
4 - Cost of actually generating energy.

An intermittent embedded (eg household, small business with solar) generator is providing item 4 most certainly. They are generating energy, that is a given.

Depending on location they may or may not also be providing items 2 and 3. That really depends on when the generating plant operates (eg solar during daytime with peak production around noon) and when demand for electricity peaks in that location (suburb or town in the case of the distribution network, state or country in the case of generation and transmission).

In SA the peak is very clearly in Summer and driven by hot weather. Solar PV thus contributes to items 2, 3 and 4 in SA up to the point where Solar PV becomes so large as to mean that the effective peak load on the system shifts to another time. That's starting to happen now, peak demand is becoming later in the afternoon, and if enough solar capacity is installed it will end up with the peak being on hot Summer evenings and cold Winter nights. At that point, further investment in small scale solar does absolutely nothing to offset cost items 2 and 3.

In Tas the peak is around 8am in Winter and driven largely by space heating. Solar makes only a minor contribution to offsetting that, solar isn't producing much under those conditions, but if enough of it was installed then it could foreseeably reduce the 8am peak enough that the secondary peak which is slightly lower, that is around 6pm in Winter, ends up being the peak as such. In Tasmania, solar PV is really only contributing to item 4, it generates energy, and in a very minor way to items 2 and 3.

Nowhere does intermittent generation contribute to item 1, the cost of having the grid there in the first place, unless it operates such that the grid is no longer required at all in some areas. That requires either firm dispatchable generation (gas, diesel, hydro, whatever) as the source of network embedded generation or alternatively requires the use of storage (eg batteries).

Unless we're going to have 100% of homes with stand alone off-grid systems then we're still going to need the grid and as such cost item 1 will still be there, along with some cost for the others.

How to pay for it is the question. In Tas the idea of separating out the cost components and charging accordingly was tried 20 years ago and let's just say that the public reaction was hostile to say the least. It ended up with pricing decisions being transferred to an independent regulator and became a major issue at the state election.

We're now approaching the point where we're going to have to go down that track again although for practical reasons, that is the extent of solar PV uptake by households, SA will be the first and Tas will likely not go there until the other states have done it (makes the politics a bit easier to manage).

As for the value of generation, well I'm very sure that large scale generation is nowhere near the cash cow that the general public seems to think it is. People get rather upset when they hear that some big factory is paying 4 cents / kWh but what they don't realise is that households are actually paying the same price. All the rest, that is the other 80% of the bill, is for the network costs. You might use 2000 kWh and pay $500 for that, but well under $100 ends up going anywhere near an actual power station. All the rest is networks and retail.

Unless they are reducing peak demand, as is the case up to a practical limit in places such as SA, then the value of intermittent generation that works well on some days and not much on others is inherently lower than the value of firm output from steam, hydro or gas turbine based power stations.

Many seem to dislike being paid 5 - 6 cents per kilowatt hour for their solar feed in. Suffice to say that large scale generators are getting considerably less. Whilst the spot price in Vic is forecast to reach as high as 9 cents / kWh tomorrow, and that's unusually high, it's also forecast to fall below 2 cents a few hours from now. Average for this financial year to date varies between states but it's in the range of 3.74 (Vic) to 5.607 (SA).

 

[Smurf1976]

If we are serious about tackling the easy parts of energy savings then a five year program to see all lights changed would be excellent.

In my view it depends on the situation.

Large businesses will, if they have any sense, have someone whose job it is to know about these things and do the numbers. They're already aggressively adopting LED's to considerable extent, and that's despite starting from a base (fluorescent) that was already reasonably efficient. Reducing maintenance costs is a key driver there, energy is only part of the equation, so it really does stack up.

Households will respond largely to what is sold for replacements. A light bulb blows, consumer buys a replacement and installs it. If what is being sold new is efficient then in a relatively short space of time all the high usage inefficient lighting is replaced given that the lifespan of a household incandescent is only 1000 hours an for halogen typically 2000 hours.

For household lighting that is rarely used, I'd argue that it's not worth worrying about. Someone has a spare bedroom and turns the light on for all of 2 hours a year. The incandescent bulb will likely never fail, but it just doesn't matter because it's using so little energy anyway. Given that CFL's and LED's are electronic devices with a practical shelf life, versus the indefinite shelf life of an incandescent or halogen lamp, there's nothing to be gained either economically or environmentally by replacing rarely used lights in homes.

Small business is where there might be a need to encourage upgrades. They don't have the resources to be focused on things like lighting, energy is usually only a minor part of their overall business costs anyway, and they lack the technical expertise and in many cases finances to evaluate and undertake improvements. That many operate from rented premises where landlords have no incentive to upgrade lighting (since they're not paying the operating cost) adds to that problem.

So I can see a benefit in encouraging upgrades in some situations, notably small business, but for large businesses the market will take care of this one and already is. For households the real issue is what gets sold by the major retailers - if they stop selling inefficient products, either due to market demand or regulation, then pretty quickly households will no longer have inefficient lighting in any higher usage applications (the ones that matter).

One potential issue is that whenever someone comes up with a new, less efficient means of lighting consumers seem to embrace it. It was halogen downlights 20 years ago, replacing a say 3 x 60W bulbs with half a dozen 50W halogens thus doubling energy consumption (those halogens also have transformer losses) and lighting the living room as bright as an office.

Now it's these carbon filament globes, a device that's half as efficient as an old incandescent bulb and which I never thought I'd see anywhere other than a science museum. They've become so popular that all sorts of commercial premises seem to have installed new lights for no purpose other than displaying these bulbs above counters and the like. I suppose it's art in a sense so I'm not complaining, just noting that if someone comes up with an inefficient way of lighting then it does seem to catch on. Maybe whale oil lamps will make a comeback....

As for me, I'm firmly in the "upgrade when it breaks" category. A CFL in the hallway certainly, that light is on quite a lot, and in due course I'll replace it with LED. On the other hand, there's just no point worrying about the lights on the patio which are on for perhaps 10 hours a year at most. There's no gain, economic or environmental, to be had there and the old bulbs will probably outlive me anyway. If a bulb hasn't blown yet, and I've lived at this address for 8 years now, then that's a pretty sure indication that the light isn't being used enough to be worried about.

 

[qldfrog]

Smurf, you common sense and lucidy is a breath of fresh air.100% agreeing on that last post; I have all types of lights , based on usage

 

[pixel]

Does anybody know the ratio of lighting requirement for -

• private dwellings
• commercial/ office space
• community/ street lighting?

When I drive at night towards the City, it strikes me how brightly the office towers are shining, although they will be practically empty; add the glaring signs outdoing each other in advertising their respective companies, and the result must be a considerable number of Megawatts.
And then there are the street lights and traffic lights.
Do our councils and traffic authorities apply the same efficiency considerations as home owners and residents? Can someone please shed some light on the issue? I only found an article that LEDs could slash street lighting consumption by 97%: http://reneweconomy.com.au/2014/leds-could-slash-street-light-energy-usage-by-97-16446
However, I am unsure whether such a move would be high on (some) Governments' agenda, given their entanglement with power producers and their desire to maximise profits...

 

[basilio]

Your quite right Smurf. There is little point in changing infrequently used lights for energy saving globes. In fact one of the "cheats" used by organisations that offer free energy saving lights is changing every light in peoples homes to maximise rebates rather than focusing on, say, 6-10 lights that are most used. There is no way replacing a light that is used for 50 hours a year will make any meaningful contribution to CO2 reduction

I was thinking about the mass commercial use of lighting when I talked about 5 year plans to change all lights. Having said that one thing that must be ensured is the life of the replacement units. I'm fed up with the industry gaming the public with new lighting technology that uses components that break down far more quickly than they need to - just to ensure repeat sales.

 

[Smurf1976]

Does anybody know the ratio of lighting requirement for -

• private dwellings
• commercial/ office space
• community/ street lighting?

Private dwellings it used to be around 7% of electricity used back in the days when it was just about all incandescent. It would be lower now. Key drivers are energy cost and perceived quality and aesthetics of the light produced, since in general labour for replacement is free and consumers tend to place a moderate value (at most) on the energy efficiency aspect.

Commercial it varies depending on the nature of the business, but for offices lighting and air-conditioning are the main loads whereas in a factory the machinery is usually the main energy user. Lighting is also the highest or second highest electrical load in places such as shops. Key drivers are energy cost and maintenance cost, noting that maintenance will almost always involve he use of paid labour.

Street lighting uses less than you might think. I don't have figures for other states but in Tas it's in the order of 0.2% of all electricity is used for street lighting. In a large city it would be more significant whereas it's negligible in a rural area with just the odd light here and there. Maintenance cost tends to outweigh energy cost considerations, hence why the old 2 x 20W fluoresecent tubes were replaced with less efficient 80W mercury vapour. Energy consumption doubled but a single MV lamp is an awful lot more reliable than two fluoro tubes such that the overall cost ends up lower. There's a recent trend to LED street lighting largely driven by political considerations (saving the planet) and aesthetics (since it's white not orange like sodium lights are - although sodium is in most cases no less efficient than LED).

 

[pixel]

Thanks Smurf;

I thought you might have the answer. And you didn't disappoint.

Now, if I get that right, and private dwellings use less than 10% of grid power - what's all the kerfuffel about power companies suffering losses because some of us save with Solar?
Or were the 7% you mentioned only for lighting? In which case the switch to fluoro and now LED would save a maximum of 7%, in other words: peanuts overall!

From my own experience, I can say that installing Solar Hot Water has made the biggest difference to our average power consumption; replacing the old 3-phase instant heater cut our average by almost a third. A little later, we replaced the incandescent globes, but the effect of that step was next to nothing - except, of course, as a maths exercise. Of course, a couple living on their own can easily adopt the habit of switching lights off where they're not needed. I also use the switches at wall sockets after turning off computers and stereo. But I suspect those habits, while they make fundamental sense, will only save pennies compared to big-ticket items such as aircon, fridge/freezer, and washing machines

 

[Smurf1976]

Consumption of households versus everything else varies between states and also seasonally.

In Tas households only use about 20% of the total energy generated. I don't have figures for the other states but in general it would be a bit higher as a % of the total but still well below 50% even in states with relatively little industry. Households are not the main driver of electricity load in most places on earth.

In practice, residential lighting would only be 1.4 to about 3% of total power generated depending on location. So there's a saving but it's not a massive one.

Commercial lighting, on the other hand, tends to run for far longer periods and often ends up somewhere approaching half the total load of a business premises in the case of things like offices or shops. That's where any major savings will be made.

 

[basilio]

Pixel don't kid yourself about the impact of incandescent lights on an energy bill. They can in fact be quite high particularly if a light is left on for long periods. Simple example

60w globe x 24 hrs =1340 kilowatts or 1.3 khwr. By way of comparison an average household would use around 10-12 kwhrs a day. A fridge uses around 1.5-2.5kwhr a day and that is normally the single largest user of energy ina household. (That's why the old beer fridge still running in the garage is costing you $150 plus a year)

You get similar figures when you add up the various amounts of power used on stand by ie TVs, microwaves. This is particularly the case for older electrical items where standby power use could be 8-15 watts per item - all running 24/7.

 

[basilio]

Commercial lighting, on the other hand, tends to run for far longer periods and often ends up somewhere approaching half the total load of a business premises in the case of things like offices or shops. That's where any major savings will be made. Smurf

Not to mention the attendant A/C load caused by the heat. And that is the market for rapidly moving to long life low energy use leds. (As long as they don't die early...)

 

[qldfrog]

http://www.bloomberg.com/news/articles/2015-12-17/what-just-happened-to-solar-and-wind-is-a-really-big-deal
US budget not so discussed but major decision on renewable

 

[sptrawler]

The problem with batteries, is they rely on a chemical reaction, which takes time and is size, density specific.

They are not the answer in their current configuration, they can't supply enough power/size and they take too long to charge.

A capacitor hybrid will be the end result, if it is achievable, otherwise it will be a fuel cell. IMO

 

[Smurf1976]

No so much the future of energy generation but the present.

In short, what is now thought to be a major fault occurred on the Basslink cable which links Vic and Tas on Sunday afternoon (20 Dec).

Investigations thus far are to the effect that the fault is not with land based equipment at either the Vic or Tas end as was initially assumed (and hoped since that would be straightforward to fix) but is a fault with the cable itself. Best estimate for the location is about 100km north of Tasmania so that's sitting on the bottom of Bass Strait.

Practical effect is that Tas and the mainland are now completely isolated electrically and running as separate grids whereas normally they are linked with power flowing in either direction as necessary.

The lights won't be going out in Tas anytime soon, there's still a few tricks left in the bag before that happens, but it does make things rather "interesting" that's for sure now that there's no option other than to supply 100% of demand from local generation.

Potential effect on supply security in Vic is harder to assess since it really depends on maximum temperatures and when they occur plus how well generation holds up in Vic and SA. Small chance that there could be a problem but will have to wait and see on that one. If the lights do go out, then it'll be on a working weekday that's 40+ degrees in Adelaide and Melbourne so not good.

Basslink is a privately owned asset and is not owned or operated by Hydro Tas or any other energy company that sells to the public. Cause of the fault is unknown at this stage apart from some estimates (based on tests conducted on shore) of the location.

 

[qldfrog]

thanks Smuf, should wind be a viable option in Tasmania, in event like this or in drought, I have the feeling hydro may need some booster.
As far as my qld view is, I do not believe there are much wind turbines built in Tassie?Am i wrong?

 

[basilio]

The breakdown in Basslink is scary as we go into a long hot summer. I was thinking as we sweltered through the record breaking heatwave last week that this wasn't the time for a power blackout.

Yet times of extreme heat are prime times for blackouts as the system is strained by maximum use, the infrastructure comes under additional pressure from extra heat loads and power companies decide to take various plants off line for maintenance. (This last situation has nothing to do with possibility that resulting pressures on demand will force up spot prices for power..)

All it needs then is a relatively small breakdown to trigger widespread power cuts which will be at times of absolute peak heat and power usage. I wonder how long many older people would survive without A/C or fans in a heatwave ?

 

[Smurf1976]

thanks Smuf, should wind be a viable option in Tasmania, in event like this or in drought, I have the feeling hydro may need some booster.
As far as my qld view is, I do not believe there are much wind turbines built in Tassie?Am i wrong?

We've got two significant wind farms in Tas, that being Woolnorth (140 MW) and Musselroe (168 MW). They are geographically dispersed with Woolnorth being at the far NW tip of Tas and Musselroe being at the far NE tip of the state. There are plenty of other sites that could be developed if the economics were right.

In the short term existing wind + hydro will carry the load and everything's OK in that regard. Things aren't great, the dams are a lot lower than would be ideal, but overall there's enough power available based on present circumstances.

Other options if needed are gas-fired generation at Bell Bay (3 of the 5 units there were given a run for a few hours today and are ready to go into base load production if required with a 4th unit being ready mid-January) and at a number of sites it's possible to draw water storages down below normal minimum levels if there's no alternative. So no blackouts, just some excitement in the media, some noise up at Bell Bay and maybe some unhappy fishermen. And then there's the cost...

What happens next really depends on rainfall and how long Basslink is out of service. They are quoting 60 days at this stage however that's simply because that's what's in Basslink's contract with Hydro Tas. Maximum outage duration is 60 days. So that's an "administrative" figure and not an "engineering" one at this stage. How long it will actually take to fix is an unknown so far but there's a lot of organising to do given that nobody in Australia has the required equipment to repair the cable (and the exact problem is itself unknown).

There are fewer options in Vic, it really comes down to what the actual peak demand is and whether or not that load can be supplied at the time. Very hard to predict that but certainly the Basslink failure does increase the chances of supply problems during a heatwave.

 

[sptrawler]

No so much the future of energy generation but the present.

In short, what is now thought to be a major fault occurred on the Basslink cable which links Vic and Tas on Sunday afternoon (20 Dec).

Investigations thus far are to the effect that the fault is not with land based equipment at either the Vic or Tas end as was initially assumed (and hoped since that would be straightforward to fix) but is a fault with the cable itself. Best estimate for the location is about 100km north of Tasmania so that's sitting on the bottom of Bass Strait.

Practical effect is that Tas and the mainland are now completely isolated electrically and running as separate grids whereas normally they are linked with power flowing in either direction as necessary.

The lights won't be going out in Tas anytime soon, there's still a few tricks left in the bag before that happens, but it does make things rather "interesting" that's for sure now that there's no option other than to supply 100% of demand from local generation.

Potential effect on supply security in Vic is harder to assess since it really depends on maximum temperatures and when they occur plus how well generation holds up in Vic and SA. Small chance that there could be a problem but will have to wait and see on that one. If the lights do go out, then it'll be on a working weekday that's 40+ degrees in Adelaide and Melbourne so not good.

Basslink is a privately owned asset and is not owned or operated by Hydro Tas or any other energy company that sells to the public. Cause of the fault is unknown at this stage apart from some estimates (based on tests conducted on shore) of the location.

It will be interesting to find out the root cause of the failure, be it mechanical, chemical or electrical. It isn't new technology, so there will be a lot of interest in the outcome.

 

[Smurf1976]

thanks Smuf, should wind be a viable option in Tasmania, in event like this or in drought, I have the feeling hydro may need some booster.

Wind right now = zero (because the wind stopped blowing).

You can generate power from wind certainly, but it doesn't really help in a crisis. You can't just decide that you're going to run the wind harder because something else stopped working and if you're unlucky then the wind stops too right at the worst possible time.

Solar - well that's not working either because it's dark.

I'm very much in favour of renewables and wind is certainly going to be a big part of that in most places. But situations like the present do highlight the need for firm, dispatchable power in the grid be it from fossil fuels, batteries, hydro or whatever.

 

[qldfrog]

Wind right now = zero (because the wind stopped blowing).

You can generate power from wind certainly, but it doesn't really help in a crisis. You can't just decide that you're going to run the wind harder because something else stopped working and if you're unlucky then the wind stops too right at the worst possible time.

Solar - well that's not working either because it's dark.

I'm very much in favour of renewables and wind is certainly going to be a big part of that in most places. But situations like the present do highlight the need for firm, dispatchable power in the grid be it from fossil fuels, batteries, hydro or whatever.

I would have thought that with the amount of hydro installed, Tasmania would have some storage capacity (pumping back in the dam) for wind production more than elsewhere in Australia. Anyway no big deal for Tassie based on your analysis, more worrying for Victoria /SA in case of a heatwave

 

[Smurf1976]

I would have thought that with the amount of hydro installed, Tasmania would have some storage capacity (pumping back in the dam) for wind production more than elsewhere in Australia.

At present, even at the extreme (maximum wind generation combined with absolute minimum system load), wind still only supplies no more than one third of the system load. That being so, we have no need to ever put energy into the hydro system in order to store it, it's simply a case of adjusting how much comes out and that never goes to zero.

Pumped storage could certainly be done at some sites (though it's more involved than simply adding pumps as such) but the system as it stands today was built for base load energy production rather than peak power and as such has no pumped storage facilities at present. There's only 3 of those in Australia presently - 1 in Qld and 2 in NSW.

We do have a number of diversion pumps in Tas however. In general terms, that's about pumping water x metres (vertically) over a hill to get it into a storage that then feeds a power station. Since the water subsequently falls many times further (vertically) than it was first pumped, that operation is energy positive as such with the amount of energy recovered being many times that used in pumping. Depending on circumstances those pumps may be run at off-peak times (daily or seasonally) but that's just a case of optimising "because we can" rather than something that's essential as such under normal circumstances.