[Scrub Puller]

Yair . . . In Australia anyway I see the possibility and advantage of solar installations on a town/village level. In theory it would be more reliable and save the cost and maintenance of thousands of miles of transmission line.

This once was the case. Many towns had their own local generation and distribution system providing a few local jobs remote from the main grid . . . it could happen again with solar.

I must say though that these last few years have seen a considerable improvement in grid reliability and, even in the stormy season our power seldom goes down . . . it is obvious though that this happy state would be in jeopardy if there was a severe downturn in world and local affairs.

Cheers.

[GHung]

The primary issue with complex, centralized energy systems, or even lager distributed systems is that they insulate individual consumers from the consequences of over-consumption. It's largely a behavioral problem. Of course, when prices rise, or things begin to run out, simple conservation becomes a forced preference, at least for some. As long as the system can provide as much as folks want, when they want it, if they can afford it (or not), that's what they'll do.

Being off-grid, or invested in one's own energy sources, has generally the opposite effect. Responsibilty for one's own comfort and survival comes into play; a powerful thing - at once, both scary and self-empowering. Becoming less reliant on a largely disfunctional collective is quite an enabling transition. My perception of things has changed in some unexpected ways.

Not everyone can do it, but what about those who can and choose not to? I doubt it's because they're worried about crashing the system via their non-participation. I suppose it's all about convenience.

[GHung]

@pstarr - Get a mixing valve; mixes cold water with hot to keep a constant DHW temp. Ours cost about $50.

Our unpressurized HW storage tank is over 400 gallons and heated with solar+solar electric+wood stove. It heats the DHW via a simple copper tubing loop in the top, and also heats our floors with water drawn directly from the tank. Tons of storage there.

@Pops - As I've posted vefore, passive solar thermal is the best investment we've made. It just works, and everything else is secondary.

[Graeme]

DOE: SUNSHOT HITTING MARK WITH SOLAR PRICE PLUNGE

$this->bbcode_second_pass_quote('', 'T')he Obama administration says that SunShot, its program to bring down the cost of solar-generated electricity to where it is competitive with conventional electricity, is 60 percent of the way toward its goal, at least when it comes to big solar.

Citing levelized cost of energy data from the National Renewable Energy Lab, the Department of Energy said on Wednesday that “the average price for a utility-scale PV project has dropped from about $0.21 per kilowatt-hour in 2010 to $0.11 per kilowatt-hour at the end of 2013.”

The DOE noted that the average retail price of electricity in the U.S. is 12 cents per kWh. That said, utility-scale solar electricity doesn’t really compete with retail electricity (whereas distributed, or rooftop solar, does) – which is why SunShot has a 2020 goal of getting solar down to 6 cents per kWh, in the neighborhood of the cost of new natural gas-fired generation.

[Graeme]

Adequate Transmission Among Options to Better Integrate Renewable Energy to Grid, Says NREL

$this->bbcode_second_pass_quote('', 'A')dequate transmission — building transmission to accommodate renewable energy, for instance — is an important component, as is energy storage, in integrating renewable energy sources to the grid, according to Lori Bird, senior analyst with the National Renewable Energy Laboratory (NREL).

Some of the major areas that regulators should keep in mind in terms of integrating renewables are market rules and public outreach, particularly for transmission investments, Bird said during a Feb. 10 panel as part of the NARUC Winter Committee Meetings held in Washington, D.C., noting that European countries have had issues with public acceptance of transmission, more so than with accepting renewable targets.

In discussing the importance of considering system operations, Bird noted that Denmark, for instance, has had very high penetrations of wind energy on its system and has been able to handle it pretty well. Some of that is because it operates in a large power pool and has a lot of flexibility in that the country has, for instance, access to Norway’s hydro plants as well as combined heat and power, which can serve as a form of thermal storage and provides additional flexibility.

In contrast, Germany has struggled with renewable integration because it has a smaller area in which to balance the system and less flexibility, Bird said. Also, Germany does not have locational marginal pricing, “so, there’s no financial impact for the congestion on the system,” she said.

Spain, she noted, has a control center for renewable energy, which is a centralized system “where they have a single point of contact with the grid operator and they’re tracking all of the output from the renewable generation and they’re able to manage very large amounts of wind power on their system.”

With respect to grid support, she noted there has been interest in Germany’s case, in which the country experienced a rapid growth in photovoltaics (PVs) and had to modify “their grid codes to make sure that they weren’t going to lose all the small PV capacity all at once on the system if there was a small frequency change on the system,” she said.

Germany had to retroactively change the inverters on the system to accommodate the PV, she said.

“[T]hat’s a lesson for other regions — to get out ahead of those [issues and] understand what’s needed in terms of grid support from these renewable facilities,” she said.

[Graeme]

Will Distributed Energy Make Up One-Third of the US Power Supply by 2020?

$this->bbcode_second_pass_quote('', 'H')ere’s a sobering thought for U.S. utilities and grid planners seeking solutions for a future filled with distributed, customer-owned energy assets: that future is already here.

That’s one way to look at a striking chart presented at the DistribuTECH smart grid conference last month. It indicates that distributed energy resources (DER), far from being a tiny fraction of the country’s massive central generation fleet, may account for up to one-third of the total U.S. electricity supply by decade’s end.

But there’s a catch -- this supply isn’t mostly made up of rooftop solar PV, or homes and business equipped with modern energy-saving, peak-shaving demand response technology. While those resources are growing fast, by far the biggest share of this untapped DER resource comes in the form of two decidedly un-sexy technologies: combined heat and power (CHP) systems and rarely used backup generators.

Here’s the chart, provided by former Southern California Edison smart grid chief and Cisco connected grid CTO Paul De Martini during a presentation hosted by grid software startup Bit Stew on the future of distribution grids:

[Graeme]

Global Renewable Energy Grid Project: Integrating Renewables via HVDC and Centralized Storage

$this->bbcode_second_pass_quote('', 'T')he global energy and environment challenges cannot be addressed through a local, regional, or even a national approach. They require a global outlook and a much broader vision, a Global Renewable Energy Grid [GREG]. A high voltage direct current [HVDC] transmission system must be built to serve as the bulk electrical power transport medium, with centralized energy storage facilities placed within GREG as needed. And perhaps most importantly, the set of socio-political overseeing institutions from each of the world’s nations needs to network together and administer just as seamlessly as the physical grid.

The obstacles to such a major global shift can be categorized as technical, economic and socio-political, with the socio-political challenges being the toughest. Researchers such as those at Stanford University have shown that adequate renewable energy resources exist to power the planet, but a detailed and comprehensive proposal for a global energy network has yet to take shape: regional planners need to combine their efforts before this can be achieved. Likewise, complete and clear rules on how to pay for a global energy grid must be established. This would require top energy administrators in each participant nation to come together under an umbrella organization at the United Nations.

After a brief overview of energy economics along with political obstacles, we offer technological suggestions as to how a global grid might be implemented. HVDC transmission is recommended as a clear choice for most efficient and reliable long-distance delivery of electrical power 24/7/52. And centralized storage mega-plants are proposed for balancing supply and demand across a network of mostly intermittent sources.

[Keith_McClary]

$this->bbcode_second_pass_quote('Graeme', '[')img]http://www.renewableenergyworld.com/assets/images/story/2014/2/11/body-4-1392147296102.png[/img]

[Graeme]

Behind-the-meter energy storage: Not hypothetical anymore

$this->bbcode_second_pass_quote('', 'O')ne of the befuddling strategic decisions that energy storage developers must make is where on the grid to place the storage assets.

Traditional utility thinking would have it all congregated in a single location: a warehouse full of batteries ready to send power to and from the grid in a centralized fashion. A decentralized approach, however, adds more value because energy storage systems can be placed at or near the load, solving both local and systemic problems. Even more valuable would be to place the devices just outside the grid, within the end user location, on the customer side of the meter -- i.e., "behind the meter." However, doing so requires significantly more communications, remote control and computing power. It also increases the cost of individual systems because the associated equipment, such as inverters, control equipment, transformers, etc, can't be shared across a lot of batteries.

There is a situation, though, in which customer-sited energy storage enables a big cost reduction: when the energy storage system shares equipment with photovoltaics. That makes both the battery system and the PV system cheaper to operate while increasing the value of both.

Throughout the world, behind-the-meter energy storage systems are starting to take off. This is primarily due to regulatory incentives that see such systems as an ideal way to allow for increased penetration of renewables, particularly solar PV, on the grid.

Regulators throughout the world have begun to favor behind-the-meter energy storage over more centralized systems, thanks to a desire to empower the ratepayers and citizens whom the regulators represent. The combination of regulatory subsidies and PV-integration are creating a modern renaissance in residential and commercial building energy storage systems.

Here are some examples of regions where the movement is in full bloom:

[Graeme]

Will the electricity grid become optional?

$this->bbcode_second_pass_quote('', 'F')or years, low-cost solar-plus-battery systems were seen as a distant possibility at best, a fringe technology not likely to be a threat to mainstream electricity delivery any time soon. By far, the limiting factor has been battery costs.
But thanks to a confluence of factors playing out across the energy industry, the reality is that affordable battery storage is coming much sooner than most people realize. That approaching day of cheaper battery storage, when combined with solar PV, has the potential to fundamentally alter the electricity landscape.

While grid-tied solar has seen dramatic recent cost declines, until recently, solar-plus-battery systems have not been considered economically viable. However, concurrent declining costs of batteries, growing maturity of solar-plus-battery systems and increasing adoption rates for these technologies are changing that. Recent media coverage, market analysis and industry discussions — including the Edison Electric Institute's January 2013 "Disruptive Challenges" (PDF) — have gone so far as to suggest that low-cost solar-plus-battery systems could one day enable customers to cut the cord with their utility and go from grid connected to grid defected.

But while more and more people are discussing solar-plus-battery systems as a potential option at some point in the distant future, there has been a scarcity of detailed analysis to quantify when and where. Until now.

[Mesuge]

Currently the *prices have fallen so hard, that it's possible to think about it in terms do I have to have new car or instead offgrid PV system + batt. storage + generator, and you can still afford some used clunker on top of it. Obviously on the condition you prioritize and cut some wastefull load in the first place. And given the increasing probability of some harder scenarios (~Seneca Cliff) this is just a 10-20yrs plan into the future anyway, but still better to have something provisional than nothing and be stuck in total dependency on the collective.
Yep, if you have no funds at all it's and advice with zero value.

*not only that on top of the bargain pricing, in some European regions, the end or some form curbing of former lush renewable tariff schemes due to budgetary concerns have sent some of these big PV parks and installers into bankruptcy, sometimes you can get this equipment stuff almost for nothing. I've seen in it around me, "poor people" are capitalizing on this rare opportunity like crazy. You should too, I'm considering, i.e. waiting for even bigger slump in the short term.. warning it's not that easy often the big park equipment is hard to re-wire for home scale system application..

[Graeme]

Navigant Research: PV Microinverter and DC optimizer market to reach 12.8 GW by 2020

$this->bbcode_second_pass_quote('', 'N')avigant Research (Boulder, Colorado, U.S.) has released a new report which finds that microinverters and DC optimizers are playing an increasingly important role in both large-scale and distributed renewable energy generation.
“Microinverters and DC Optimizers” also finds that as these technologies have the potential to increase grid reliability. Navigant expects annual installations of module-level power electronics (MLPE) to grow eleven-fold by 2020 to 12.8 GW, for a total of 52.7 GW over seven years.

[Graeme]

Can you provide a reference? Lithium battery tech is improving (e.g. see here).

$this->bbcode_second_pass_quote('', 'T')his new pomegranate design further works on that research and could be commercialized in batteries for cell phones, tablets and even electric cars. In experiments the team says that the structure holds up with 97 percent capacity after 1,000 cycles. The carbon rind around the silicon pomegranate seeds enables electrical current but protects the silicon from reacting with the electrolyte.

[Graeme]

This thread is not about energy storage. Go to "Prospects for large-scale energy storage" thread and you will see that there is an increasing demand for it. I suspect that the type of storage will partly depend on individual circumstances, and other factors like cost, efficiency and as you mention capacity. The field is rapidly developing and I am struggling to keep up with it. Allied to this is the increasing deployment of distributed solar, which is what this thread is about. Musk sees the demise of centralized solar but don't think that this will be the case. As I mentioned at beginning of thread, I think that both will be required. But we'll see as I find further developments. This issue is not going away.

[Graeme]

Maybe you could ask your solar panel provider if they also offer batteries for storage. Here are some providers that offer batteries:

$this->bbcode_second_pass_quote('', 'S')olarCity Corp., Kyocera Solar Inc., S&C Electric Co., Standard Solar Inc. and Blackstone Group’s Vivint Solar unit have also expanded their rooftop solar offerings to include battery storage.