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Have a look at this as part of the solution (the smart mobile metering):

http://www.earth.org.uk/note-o...

and another company I know well, Upside:

https://upsideenergy.co.uk/

I also think that we're missing some smaller-scale software-based solutions available already:

http://www.earth.org.uk/Hey-Si...

Rgds

Damon

Have a look at this as part of the solution (the smart mobile metering):

http://www.earth.org.uk/note-o...

and another company I know well, Upside:

https://upsideenergy.co.uk/

I also think that we're missing some smaller-scale software-based solutions available already:

http://www.earth.org.uk/Hey-Si...

Rgds

Damon

I run a similar setup (ie my entire primary server set including HTTP, NTP, DNS, etc) on an RPi2.

Does its job very well and uses only 1W most of the time enabling me to keep them off-grid:

http://www.earth.org.uk/note-o...

http://www.earth.org.uk/_off-g...

I see various people pissing all over the RPis here, but they really are remarkable, and bigger is not always better. It depends on the application.

Rgds

Damon

I run a similar setup (ie my entire primary server set including HTTP, NTP, DNS, etc) on an RPi2.

Does its job very well and uses only 1W most of the time enabling me to keep them off-grid:

http://www.earth.org.uk/note-o...

http://www.earth.org.uk/_off-g...

I see various people pissing all over the RPis here, but they really are remarkable, and bigger is not always better. It depends on the application.

Rgds

Damon

Here was one I wrote up at the weekend:

http://www.earth.org.uk/Hey-Si...

Guess what could compute a daily forecast ready to upload to those phones and laptops, just for example, as well as some real-time polling?

Some of it could be based on the data used here:

http://www.earth.org.uk/_gridC...

Rgds

Damon

Here was one I wrote up at the weekend:

http://www.earth.org.uk/Hey-Si...

Guess what could compute a daily forecast ready to upload to those phones and laptops, just for example, as well as some real-time polling?

Some of it could be based on the data used here:

http://www.earth.org.uk/_gridC...

Rgds

Damon

The harsh / glorious reality hasn't changed. If you want to get real work done it's going to be on a desktop.

Depends what you mean by "real". Yes, I got paid megabuck(s) in banking to optimise quant algos across cores, CPUs and servers in (eg) the Credit dept at Lehman's, but I find my nominally underpowered MacBook Air (the saleswoman was slightly reluctant to sell it to me when I said I was a dev) to generally be damn good for what I need, including some decent data driven models and analysis, wrapped in not-even-optimised C++ unit tests, and running within a Java-based IDE!

So, horses for courses.

Also, I am the happy owner of an RPi that does all the work a Sun server farm used to do for me:

http://www.earth.org.uk/note-o...

and I target my primary code to 8-bit MCUs similar to a Z80A form 30Y ago in power, running some nice slim highly-optimised distributed coding.

Cut your suit to fit your cloth.

Rgds

Damon

Exactly so; cf 5% in distribution and 2% in transmission for the UK typically, so far from a deal breaker.

Indeed it might be worth a transmission link across the Atlantic IMHO:

http://www.earth.org.uk/note-o...

But obviously it's better to shout things down while admitting never even trying to find the facts...

Rgds

Damon

HVDC transmission losses are of the order of a couple of % per 1000km IIRC. So, yes, we have a solution to the transport problem called "interconnectors" which I've no reason to believe is overly ambitious.

If you want ambitious, try:

http://www.earth.org.uk/note-o...

Rgds

Daomn

I use an RPI as my primary Internet facing server and for other tasks, and matches the performance of a rackful of old Sun equipment. And runs from off-grid solar power, ie orders of magnitude less than those Sun servers:

http://www.earth.org.uk/off-gr...

Oh, and I can shove it in a small cupboard, rather than taking a whole room.

And I run it fanless with entirely solid-state media, so it's quiet.

So, smaller, quieter and vastly more energy efficient and cheaper and people are WHINING?

Gah

Damon

Hi

We're working on a project (in public) to try to help secure out-of-the-box links from low-power cheap sensor nodes to the concentrator (or equivalent) in IoT networks.

Eg see:

http://www.earth.org.uk/note-o...
and
http://lists.opentrv.org.uk/pi...

to pick a couple of related items.

Anyone who'd like to help us get this right with solutions open source, please do contact us eg via @OpenTRV on Twitter or email.

Rgds

Damon

Note: skylights are poor thermally and let a lot of heat out. Also I had one in a previous house in the bathroom where the seal was so bad (thus clearly leaking air too) that I had the surreal experience of being hailed on in the bath.

Also, have skylights ways from south (if you're in the northern hemisphere) to avoid excessive glare and overheating.

BTW, I have triple glazing now! Overall heat consumption from natural gas was 3000kWh last year and electricity 1700kWh.

http://www.earth.org.uk/saving...

Rgds

Damon

EU regulations require appliances in actual standby to use no more than 0.1W, which is less than a neon indicator bulb, and *is* good.

My cable TV box uses 15W and consequently I make sure that it is turned off completely, along with TV and DVD else it would be responsible for ~10W of our entire electricity bill.

http://www.earth.org.uk/saving...

I have prototype voice detection circuit sitting on my bend that is using tens of microwatts to detect occupancy, so milliwatts should be plenty to do the instant-on job for those too damn idle to press a button.

tl;dr: 10W is *crap* for an always-on device doing nothing.

Rgds

Damon

We don't have peak demand from aircon in the UK (GB grid) either. Ours comes on (winter) evenings when, for example, meals are being cooked for kids home from school.

Do you have a link to your utility's site?

Yes, of course you shouldn't take my word on spec over your local guy's, but I'm stubbornly continuing to assert that your local load profile can't be completely flat and with rock-steady frequency even if not as tortured as elsewhere.

For reference here's my 'local' grid (GB) live balancing stats:

http://www.bmreports.com/bsp/b...

I am truly sympathetic to your wish to overcomplicating things and making them more complex and fragile: I just don't think this stuff will be 'over'-complexity for a huge chunk of the purchasers, it will be more like an essential and pay for itself in upfront balancing payments off the purchase cost in many cases.

Here are a few of my wacky ideas on the topic, one of which got me through the first round of a competition sponsored by National Grid and another of which has been discussed with an electricity supplier:

http://www.earth.org.uk/domest...

I will still try to turn some of these into niche (but simple) versions of consumer products. You only buy these ones if they meet a need for you and no one else is lumbered with the extra complexity...

Rgds

Damon

Neither your house nor your fridge maintain an absolutely constant temperature; they cycle in a "deadband" about a set-point.

Neither your house nor your fridge instantly go to pieces thermally if you cut the power; they both have (valuable) thermal mass.

Simply widening the deadband a little, too little for there to be any functional difference, and probably for you to never notice, can make a significant difference to the grid and to your bills. The point is to slightly adjust an automatic cycle that you pay no attention to anyway to better share a scare resource.

People who are prepared to let these things happen are likely to have bills significantly, even 3x in some predictions, lower than those that don't, in a matter of a few years in some cases.

Rgds

Damon

PS. I have skin in the game. The OpenTRV project that I lead (http://opentrv.org.uk/ and http://www.earth.org.uk/open-s... for a more geeky page) aims to as much as halve space heating costs and footprint by this sort of trick while aiming to *improve* comfort by delivering heat when it is actually needed/wanted. There will also be a simple tie-in with the grid that could save up to ~2GW of peak electricity demand from UK domestic *gas* space-heating systems without most people ever noticing. That's bigger than our biggest nuke.

I have my RPi B+ running all my Internet facing services and running off-grid in gloomy London at under 2W, nearer 1.5W when I can fix some transient issues.

http://www.earth.org.uk/off-gr...

And if I need something lower power I have Arduino-like boards that I run on microwatts, eg for battery-powered remote sensing.

http://www.earth.org.uk/out/ho...

I see all the complaining about memory and speed but as someone who grew up with a Z80- and 6502- based set of home computers, then used Sun Workstations with a few MB of RAM and tens of MHz clock, the Arduino/ATMega328P matches the Z80/6502s in performance at a millionth the power and has non-volatile storage built in, and the RPis are and order or two of magnitude better than the workstations and a couple of orders of magnitude cheaper.

I can fit almost all that I need to run with careful use of resources into the RPi/Arduino world and still have lots of elbowroom left over.

Yes, I've worked on big systems for (eg) big banks, but most of us really need GHz and GB on every machine? Some yes (like my MacBook), but most no.

Rgds

Damon

I have my RPi B+ running all my Internet facing services and running off-grid in gloomy London at under 2W, nearer 1.5W when I can fix some transient issues.

http://www.earth.org.uk/off-gr...

And if I need something lower power I have Arduino-like boards that I run on microwatts, eg for battery-powered remote sensing.

http://www.earth.org.uk/out/ho...

I see all the complaining about memory and speed but as someone who grew up with a Z80- and 6502- based set of home computers, then used Sun Workstations with a few MB of RAM and tens of MHz clock, the Arduino/ATMega328P matches the Z80/6502s in performance at a millionth the power and has non-volatile storage built in, and the RPis are and order or two of magnitude better than the workstations and a couple of orders of magnitude cheaper.

I can fit almost all that I need to run with careful use of resources into the RPi/Arduino world and still have lots of elbowroom left over.

Yes, I've worked on big systems for (eg) big banks, but most of us really need GHz and GB on every machine? Some yes (like my MacBook), but most no.

Rgds

Damon

Hydro storage is pumped with whatever fuel is powering the grid at that moment, for which the ratio was only about 2:1 nuke:wind in the UK last night as it happens:

http://www.earth.org.uk/_gridCarbonIntensityGB.html

http://www.bmreports.com/bsp/bsp_home.htm

Rgds

Damon

Cheapest in terms of utility costs and thus also to you would be a flat demand 'curve', and once that was achieved then great, your work is done, but loads continue to need to be run at these new times to maintain that flat line.

However, with intermittent renewables being added to the grid another GoodThing(TM) is to match consumption to available generation.

In fact I try to shift big loads (washing machine and dishwasher) to periods where the CO2 emitted per kWh (carbon intensity) is as low as possible, in the wee hours and/or when wind generation is particularly high, see my live chart: http://www.earth.org.uk/_gridCarbonIntensityGB.html

I have also arranged to work from home much of the time, so I *can* organise when I do things, and certainly don't have to do a 9--5 bracketed by commutes each working day.

Rgds

Damon

http://www.earth.org.uk/towards-a-LZC-office.html

covers most of that. Note that there were three rounds of install.

Rgds

Damon

Hi,

Here's the project: http://www.earth.org.uk/LiFePO4-battery-testing-with-solar-PV-off-grid-system.html

I went to see the vendor at its office because it had some interesting stuff on sale, and discussing what they were working on stumbled upon this LiFePO4 battery. It's prismatic (so compact) and has a BMS built in, suitable to accept nominal 12V solar PV directly at its inputs. (It has 4 wires; PV in and nominal 12V out, though a common +ve rather than -ve which is a slight nuisance.) BMS, ie solar charging of Li, was my big worry at the time.

Rgds

Damon

Running a busy USENET server (I think I hovered at ~#10 in the stats for while) used to wear out normal hard drives too, back in the day; SSDs aren't especially novel in that regard IMHO. It's really only a matter of how frequent and comprehensive your backups are.

And as my USENET data didn't last longer than about a week then I think I regarded backups as largely pointless except for some very low-traffic local groups and just threw away a drive when it died and let the new one fill up again!

BTW, I've been running a server entirely on a mixture of SD cards and USB Flash for a couple of years so far, so good. I have taken efforts to reduce spurious writes but I still make sure that I have backups of critical stuff elsewhere: http://www.earth.org.uk/note-on-SheevaPlug-setup.html

Rgds

Damon

Indeed, my family (2 adults 2 kids) lives in 76m^2 in the London 'burbs with no problem at all, and we seem with a little effort to be in the most efficient few percent of UK housing stock for energy, at least per capita. Hate to try that with a big place. We do Freegle/Freecycle junk regularly which helps avoid wasting space.

http://www.earth.org.uk/saving-electricity.html#meter2011

We don't have a car or parking space, but we do have a small garden (well, two).

Rgds

Damon

No, I'm hitting your points on the head IMHO.

I still "can't afford" a car. I decided that PV was more important to me over the last few years for example. And yes I see PV going up on roofs around me (and I'm working to make it happen faster).

Typical install cost of a typical 2.5kWp installation in the UK is now ~£10,000, which would probably be not far off $10,000 in the US like-for-like. That system will deliver about 50% of typical UK household's electricity consumption BTW, so you might have to double it to match a US household's usage, but conservation isn't that hard (we cut from 3x mean to 0.5x mean since 2007, see http://www.earth.org.uk/saving-electricity.html for details).

I haggled my last PV system down in price by a factor of two: it's handy to know that deflation is happening and then force your installer to share their otherwise-inflated margin with you.

Rgds

Damon

Apples and oranges for your solar thermal and PV: the former gathers low-grade heat and the latter high-grade electricity. 1kWh of electricity can provide far more than 1kWh of usable heat (see the definition of a heat-pumps's Coefficient of Performance) and indeed the ratio is about that between PV and thermal nominal capture efficiency. (ST is more like 50% capture efficiency AFAIK, BTW.)

And I have my (small) roof covered with PV that generates twice what we consume in a year to make us net-zero-carbon. I don't see what you think is going to go obsolete about the grid or grid-tie inverters in the next decade which should cover my financial payback (though I don't much care about that as it happens). Inverters are nothing like as expensive as you seem to imagine.

Here's my site which covers what I've done: http://www.earth.org.uk/

Rgds

Damon

I am sitting in my aerogel-drylined living room now.

It's not quite as dramatic as you say, but two of us in here can easily maintain a 10C+ temperature differential from outside. (Wall U value now ~0.23W/Km^2.)

http://www.earth.org.uk/superinsulating-our-living-room.html

Rgds

Damon

PS. With this and other measures we've roughly halved our heating demand, even in the teeth of the harshest winters in many years.

No, not at all.

Some demand control is emergency stuff and not to be used too often, but *normal* everyday demand control is stuff like peak shaving/shifting and frequency response and is run-of-the mill non-emergency management and could be extended and would make the grid 'stiffer' and more stable, eg:

http://www.earth.org.uk/note-on-dynamic-demand-value.html

Rgds

Damon

The SheevaPlug is great: I've come down from over 600W for a rack of Solaris servers via 18W for a Linux laptop to now under 4W for a SheevaPlug (all quiet/typical consumption) to provide the same services, see:

http://www.earth.org.uk/note-on-SheevaPlug-setup.html

(Served off the plug indeed...)

I've reduced the consumption so much that the plug now runs entirely off-grid from a small array of solar PV panels (under 200Wp) with a small (12V, 40Ah) battery to cover nights and very dull days...

Rgds

Damon

I'm about halfway through moving my main server onto a SheevaPlug: a fairly stock Linux (2.6.31) with three lots of solid-state (flash) storage totalling ~160GB: it boots in ~30s (I just timed it 5 minutes ago).

Rgds

Damon

PS. It only consumes 2.5W when quiet, and runs entirely from off-grid solar power: http://www.earth.org.uk/note-on-SheevaPlug-setup.html

PPS. Yes, I know it's not Windows and it's not 1s, but we don't have to live with 20-minute reboot times these days...

Hi,

Shark should be ready by December so Xerxes Ranby tells me.

For now I'm evaluating Sun's embedded SE JRE for ARMv5 and though it only has a C1 (client) compiler it works pretty well.

http://www.earth.org.uk/note-on-SheevaPlug-setup.html#Java

Rgds

Damon

Hi,

I'm in the process of moving my main Internet-facing server onto an ARM-based SheevaPlug (1.2GHz, 512MB memory) that consumes 3W--5W (pegged at 5W right now doing a large Java build/obfuscation).

http://plugcomputer.org/

http://www.earth.org.uk/note-on-SheevaPlug-setup.html

Rgds

Damon

I love the entirely ignorant and self-absorbed "I'm alright Jack" and "Keep the Gubmint Outta My Fridge" and "I want the right to burn dioxins on my own lawn" comments.

Goodness.

For a start there's at least two sorts of appliance smartness that are useful.

1) For example, load-shifting use until there is low demand on the gird. Sometimes that electricity can be practically free (or even negative price) and reduces infrastructure costs (hardware built to cope with a smaller peak) and reduces use of often dirty and expensive 'peaking' plant. You don't have to subscribe to Climate Change to see this as a good idea. And yes, for the average family home the main candidates are the dishwasher and the washing machine. Just avoiding running your dishwasher right after dinner (until you go to bed or optimally ~3am) in the UK right now saves circa 100g CO2 emissions each time for no inconvenience at all usually:

http://www.earth.org.uk/note-on-UK-grid-CO2-intensity-variations.html

http://www.earth.org.uk/_gridCarbonIntensityGB.html

And indeed right now since the highs and the lows are at fairly fixed times then a simple timer will do a good job: not much Big Brother smartness there.

But as more intermittent power such as wind comes on line, those 'excess power available' moments will be less predictable. A really smart dishwasher lets you run it just when you want to, but if you're not in a hurry you could set it for "make sure it's done by the morning, but try to pick the time for minimum costs/emissions". I already do this in my house.

2) Balancing the grid cycle by cycle is a separate issue. In the UK fridge/freezers alone correspond to a base load of ~2GW. If a 'smart' fridge notes that the power frequency has dropped because the grid is struggling then it can postpone restarting the compressor so as to stay within normal temperature limits but coast a little while on its store of 'cool'. It might also suspend any auto-defrost for example. That helps keep the house lights on (yours and everybody else's) without spoiling your butter or denying you any rights at all. Last year we had a major nuke trip out in the UK and 500,000 people across the UK were 'load shed' and lost supply entirely. If all the fridges had been smart they may well have stayed on line without anyone noticing.

http://www.earth.org.uk/note-on-dynamic-demand-value.html

Hyperventilating about "communists" turning off the lights and freezer is so childish I find again /. posts failing to meet the IQ levels that I assumed were necessary to type. %-P

This is not to deny that such a mechanism can be royally f**ked up by individual governments and utilities, but going purple in the face while ignoring that the alternatives may well include more blackouts or higher prices, even ignoring climate-change issues, doesn't help.

Note: I already do some of this at home. I still haven't voted communist (though they may have had a local candidate here for the last elections).

Rgds

Damon

I love the entirely ignorant and self-absorbed "I'm alright Jack" and "Keep the Gubmint Outta My Fridge" and "I want the right to burn dioxins on my own lawn" comments.

Goodness.

For a start there's at least two sorts of appliance smartness that are useful.

1) For example, load-shifting use until there is low demand on the gird. Sometimes that electricity can be practically free (or even negative price) and reduces infrastructure costs (hardware built to cope with a smaller peak) and reduces use of often dirty and expensive 'peaking' plant. You don't have to subscribe to Climate Change to see this as a good idea. And yes, for the average family home the main candidates are the dishwasher and the washing machine. Just avoiding running your dishwasher right after dinner (until you go to bed or optimally ~3am) in the UK right now saves circa 100g CO2 emissions each time for no inconvenience at all usually:

http://www.earth.org.uk/note-on-UK-grid-CO2-intensity-variations.html

http://www.earth.org.uk/_gridCarbonIntensityGB.html

And indeed right now since the highs and the lows are at fairly fixed times then a simple timer will do a good job: not much Big Brother smartness there.

But as more intermittent power such as wind comes on line, those 'excess power available' moments will be less predictable. A really smart dishwasher lets you run it just when you want to, but if you're not in a hurry you could set it for "make sure it's done by the morning, but try to pick the time for minimum costs/emissions". I already do this in my house.

2) Balancing the grid cycle by cycle is a separate issue. In the UK fridge/freezers alone correspond to a base load of ~2GW. If a 'smart' fridge notes that the power frequency has dropped because the grid is struggling then it can postpone restarting the compressor so as to stay within normal temperature limits but coast a little while on its store of 'cool'. It might also suspend any auto-defrost for example. That helps keep the house lights on (yours and everybody else's) without spoiling your butter or denying you any rights at all. Last year we had a major nuke trip out in the UK and 500,000 people across the UK were 'load shed' and lost supply entirely. If all the fridges had been smart they may well have stayed on line without anyone noticing.

http://www.earth.org.uk/note-on-dynamic-demand-value.html

Hyperventilating about "communists" turning off the lights and freezer is so childish I find again /. posts failing to meet the IQ levels that I assumed were necessary to type. %-P

This is not to deny that such a mechanism can be royally f**ked up by individual governments and utilities, but going purple in the face while ignoring that the alternatives may well include more blackouts or higher prices, even ignoring climate-change issues, doesn't help.

Note: I already do some of this at home. I still haven't voted communist (though they may have had a local candidate here for the last elections).

Rgds

Damon

I love the entirely ignorant and self-absorbed "I'm alright Jack" and "Keep the Gubmint Outta My Fridge" and "I want the right to burn dioxins on my own lawn" comments.

Goodness.

For a start there's at least two sorts of appliance smartness that are useful.

1) For example, load-shifting use until there is low demand on the gird. Sometimes that electricity can be practically free (or even negative price) and reduces infrastructure costs (hardware built to cope with a smaller peak) and reduces use of often dirty and expensive 'peaking' plant. You don't have to subscribe to Climate Change to see this as a good idea. And yes, for the average family home the main candidates are the dishwasher and the washing machine. Just avoiding running your dishwasher right after dinner (until you go to bed or optimally ~3am) in the UK right now saves circa 100g CO2 emissions each time for no inconvenience at all usually:

http://www.earth.org.uk/note-on-UK-grid-CO2-intensity-variations.html

http://www.earth.org.uk/_gridCarbonIntensityGB.html

And indeed right now since the highs and the lows are at fairly fixed times then a simple timer will do a good job: not much Big Brother smartness there.

But as more intermittent power such as wind comes on line, those 'excess power available' moments will be less predictable. A really smart dishwasher lets you run it just when you want to, but if you're not in a hurry you could set it for "make sure it's done by the morning, but try to pick the time for minimum costs/emissions". I already do this in my house.

2) Balancing the grid cycle by cycle is a separate issue. In the UK fridge/freezers alone correspond to a base load of ~2GW. If a 'smart' fridge notes that the power frequency has dropped because the grid is struggling then it can postpone restarting the compressor so as to stay within normal temperature limits but coast a little while on its store of 'cool'. It might also suspend any auto-defrost for example. That helps keep the house lights on (yours and everybody else's) without spoiling your butter or denying you any rights at all. Last year we had a major nuke trip out in the UK and 500,000 people across the UK were 'load shed' and lost supply entirely. If all the fridges had been smart they may well have stayed on line without anyone noticing.

http://www.earth.org.uk/note-on-dynamic-demand-value.html

Hyperventilating about "communists" turning off the lights and freezer is so childish I find again /. posts failing to meet the IQ levels that I assumed were necessary to type. %-P

This is not to deny that such a mechanism can be royally f**ked up by individual governments and utilities, but going purple in the face while ignoring that the alternatives may well include more blackouts or higher prices, even ignoring climate-change issues, doesn't help.

Note: I already do some of this at home. I still haven't voted communist (though they may have had a local candidate here for the last elections).

Rgds

Damon

Hi,

Have a look at http://www.withouthotair.com/ where Prof MacKay deals with this.

In practice you can mitigate the problem (which will only be a problem at all in dense population areas) by capturing solar heat in summer, eg excess not needed for solar hot water, and using that to warm the ground. Then the ground is a straight-forward heat-store, maybe a little like this: http://www.earth.org.uk/milk-tanker-thermal-store.html

Rgds

Damon

http://www.earth.org.uk/note-on-dynamic-demand-value.html

Rgds

Damon

Nah, use a laptop...

http://www.earth.org.uk/low-power-laptop.html

My main Internet server (for that page for example) is well under 20W and running a couple of Java VMs and all the rest...

Rgds

Damon

Hi,

I'm here to quibble with "SSDs are always going to be for secondary computers, and portable devices."

http://www.earth.org.uk/low-power-laptop.html

I already use SSD (4GB SD card) as my primary Linux boot/main storage device to keep power consumption of my primary HTTP/SMTP/NTP/... Internet-facing server to under 20W. I also have a 160GB HDD, spun down as much as possible, for bulk data.

If this 160GB drive had existed in the middle of last year when I speced the machine, I'd have had bought it like a shot to simplify life no end (and save a little more power). Laptop-mode - who needs it? (Actually it still might save a little power by batching and conflating operations, but much less I imagine.)

Rgds

Damon

This is what I already do for my primary Net-facing server. Boot and most-frequently-accessed stuff on a 4GB SD card, the rest on the HDD which sleeps most of the time.

http://www.earth.org.uk/low-power-laptop.html

This is what I already do for my primary Net-facing server. Boot and most-frequently-accessed stuff on a 4GB SD card, the rest on the HDD which sleeps most of the time.

http://www.earth.org.uk/low-power-laptop.html

Rgds

Damon

I already boot my low-power Linux server off CF:

http://www.earth.org.uk/low-power-laptop.html

Rgds

Damon

Well, there's been a lot of heat and little light so far...

I've actually been exchanging emails with the UK's National Grid on a very similar topic: if I add some extra batteries to a grid-tie/UPS solar PV system, are they interested in it for frequency/fast standby support? Nominally I could automatically switch it on in one cycle to pump back at maximum for 30 minutes or more, which meets several of their key requirements. (See towards bottom of this page: http://www.earth.org.uk/saving-electricity.html under From Net-Zero Electricity to Negative-Carbon.)

So, I'd get paid for the electricity AND for providing a standby service to help grid stability.

1) Even if you don't cycle batteries they still have a finite life: use them or loose them.

2) You could easily set your system so that if the batteries are below 90% charge you won't support the grid: you'd hardly ever notice diminished capacity and you'd still be able to make a significant stability and peak-shaving contribution, and you'd also avoid deep-cycling for the grid which would wear them out faster.

3) You avoid frying linespeople in a power cut with a system approved to G83/1 or similar: this is old tech.

Rgds

Damon

Dead right.

It's totally unglamorous, but relatively easy. I managed to cut our home (and home-office) consumption from 33kWh/day (very high, from powering lots of Internet-facing servers) to 7kWh/day (fairly low: typical for a UK household is between 11kWh/day and 20kWh/dayt depending on whose figures you use) without any significant pain or loss of services etc.

http://www.earth.org.uk/saving-electricity.html

Most people could make significant cuts in their own consumption at home and work with zero or minimal spend and without giving up anything they currently do if they (a) wanted to (b) had the information. That's much better than technical fixes alone. One result of a US-based utility study was that simply telling people what they were using when and what it cost to generate helped cut their consumption 10%--15%. (And 78.35435102% of all such stats are hotly contested, natch...)

And there are slightly smarter things than just saving power and money that you can do if you feel inclined, which cost you nothing at all and make a disproportionate saving in CO2 and an improvement in grid stability, eg don't run big appliances at peak demand if you can easily avoid it.

For example, peak demand in the UK is in winter from 4pm to 8pm. At home we're avoiding running our washing machine and dishwasher in that 4 hour window since providing power to us (and everyone else then) is probably the dirtiest and most carbon-intense and expensive of the whole year, and with the biggest losses and strain in the distribution network. We're not sitting in the dark and cold humming whalesong: we just put off running the dishwasher for an hour or two. No one will ever notice, and our electricity bill will be just the same, so I want my medal now, of course! B^>

Rgds

Damon

http://www.earth.org.uk/low-power-laptop.html

And the site is hosted by the new equipment!

Rgds

Damon

Probably quite power-efficient with that chipset so long as they have a recent (tickless) kernel in it, such as with Gutsy, though I would like a little more memory for one of my apps:

http://www.earth.org.uk/low-power-laptop.html

Might also do nicely as an off-the-shelf monitoring device for networks, HVAC, etc...

If they sell one at a similar price here I might buy one to play with.

Rgds

Damon

Hi,

I already boot/run my main Internet-facing server (Ubuntu) from a 4GB memory SSD card to minimise power consumption, and I have more than 50% space free, ie it wasn't that hard to do.

http://www.earth.org.uk/low-power-laptop.html

I'm not being that clever about it: using efs3 rather than any wear-leveling SSD-friendly fs, and simply minimising spurious write activity, eg by turning down verbosity on logs. And laptop-mode helps a lot of course.

Now that machine does also have a 160GB HDD for infrequently-accessed bulk data (so the HDD is spun down most of the time and a power-conserving sleep mode), and it would be good to get that data onto SSD too. But a blend, as in many memory/storage systems, gives a good chunk of maximum performance and power savings for reasonable cost.

Rgds

Damon

For example, the statement about solar panels not having to be flat already applies: there are flexible, stickable (see the UniSolar laminate for example) ones now, with Fresnel lenses etc.

In fact, for many uses, solar is easily laid on an existing flat surface such as a roof. Flat is very often convenient.

The issue about capturing light from any angle is only valid if the individual cells/balls and their connectors (and any surrounding obstacles such as walls and trees) don't get in the way. Multi-layer cells and mechanical trackers and even mirrors mitigate these problems in existing systems: http://www.earth.org.uk/note-on-solar-PV-for-diffuse-light.html

Anyway, interesting, and it would be good to test some in places like the tops of walls, roof ridges, pathways, etc.

Rgds

Damon

More than a factor of four in my case (more than 20x by some narrow measures):

http://www.earth.org.uk/low-power-laptop.html

and

http://www.earth.org.uk/saving-electricity.html

Basically I replaced my entire 670W rack of Web-facing servers at home with a single Linux laptop that uses ~18W off 12V DC (+7W wasted in the mains adaptor), which sometimes now runs off-grid on solar PV so that 12V DC power figure is meaningful.

I have no reason to believe that my situation is really exceptional, and I'm running a fairly standard mix of servers (NTP, SMTP, DNS, HTTP both flat-file and Java-based)...

Rgds

Damon

More than a factor of four in my case (more than 20x by some narrow measures):

http://www.earth.org.uk/low-power-laptop.html

and

http://www.earth.org.uk/saving-electricity.html

Basically I replaced my entire 670W rack of Web-facing servers at home with a single Linux laptop that uses ~18W off 12V DC (+7W wasted in the mains adaptor), which sometimes now runs off-grid on solar PV so that 12V DC power figure is meaningful.

I have no reason to believe that my situation is really exceptional, and I'm running a fairly standard mix of servers (NTP, SMTP, DNS, HTTP both flat-file and Java-based)...

Rgds

Damon

As to Java: I have just moved a rack of (Solaris) servers @670W on to a single (Linux) laptop @18W (~25W from mains, but sometimes it runs off-grid on solar PV).

http://www.earth.org.uk/low-power-laptop.html

I actually now control the CPU-speed control with another small Java app (see update for 2007/08/20 on same page) and in particular watching it with strace() can't see the JVM doing anything that hand-crafted C wouldn't in the main loop.

In fact, the whole machine, including several Java and static Web servers, sendmail, etc, comes in at under 1% utilisation.

So Java and C at least are capable of being reasonably efficient providing the apps are written not to be profligate (I did a set of tweaks to minimise power-hungry CPU use unless there is 'excess'/spare power available from solar).

Rgds

Damon