In order to stay reliable, the national grid needs large energy storage systems that use ‘consistent’ sources of energy.

Both wind turbines and solar power are great for consumers, and the environment. But because of their intermittent nature, they need to be backed up by battery storage.

And although we think of batteries as those little cylinders we buy in the supermarket, there are other ways to store the massive amounts of energy needed by the electricity grid as we use more renewable sources.

Let’s take a look at four ways we can store renewable energy to draw on later, after the sun has gone down and the wind dies.

Types of energy storage systems

Water storage with pumped hydro
Pumped hydro storage uses renewable electricity to pump dam water to a high reservoir. When needed, energy flows back down through turbines to turn the trapped energy into electricity again.

Two large hydro storage projects are under development in Australia – Snowy 2.0 and Hydro Tasmania.

The first will connect the Talbingo and Tantangara reservoirs with a 27-kilometre tunnel, costing between $1.9 and $2.25 million per megawatt.

Hydro Tasmania, on the other hand, will turn the state into the “battery of the nation”. It will pump hydro across 14 possible sites around the state at a lower build cost than Snowy 2.0.

The main difference is the storage capacity. Snowy 2.0 aims to store 175 hours’ worth of energy, while Hydro Tasmania could only hold between 8 and 36 hours.

Molten salt energy storage systems
In South Australia, a project called Aurora will use molten salt to generate and store energy. The project requires a 240-metre-tall tower in the centre of 12,000 heliostats, or mirrors, across 700 hectares.

The sparkling green hydrogen economy of the future is a long way off, but meanwhile scientists at the Weizmann Institute of Science in Israel are hot on the trail of a hydrogen-based energy storage system that could resolve at least two significant obstacles: safety and cost.

Before we dive in the usual caveat applies: hydrogen fuel cell electric vehicles are lagging far behind their battery-powered cousins in terms of mass market appeal, but hydrogen has innumerable other uses as a fuel and industrial chemical. The global race is on to produce, store, and transport renewable H2 at scale.

Mother Nature’s Energy Storage System

The next time you walk past your house plant, give it a thumbs-up for its ability to effortlessly store energy in the form of hydrogen without setting itself on fire or blowing itself up.

Here’s an explainer from our friends over at Science Daily:

…In biological cells, finely adjusted chemical compounds bind and release hydrogen to build up the chemical compounds needed by the cells. All these biological processes are catalyzed by enzymes.

The tricky part comes in where scientists try to replicate 700 million years of evolution within a few years of lab work, and translate that into an artificial system that can be scaled up to massive proportions.

Here Comes The Hydrogen Economy…
One interesting breakthrough occurred back in 2013 a research team at Virginia Tech developed an enzyme-based formula for extracting H2 from biomass, using the common plant sugar xylose as a springboard.

Our friends over at Wikipedia note that xylose comes in several forms. Here’s one that explains why researchers have been eyeballing plants for H2 production and energy storage: HOCH2(CH(OH))3CHO.

It’s undeniable that humanity’s dependence on fossil fuels needs to change if we are going to mitigate the disastrous impact of climate change. One of the best alternative energy sources is solar power because it is so plentiful–to meet the Earth’s current energy needs, we would only need .025% of the energy the sun emits every year. It’s also cheap: If you can put the infrastructure in place to collect and store it, the solar energy itself is free.

But incentivizing people to build that infrastructure remains a challenge. Ikea’s innovation lab Space10 is envisioning a new prototype for how solar energy could be installed in local communities and then shared on a small microgrid. The microgrid would enable people to sell their excess energy to others on a blockchain-powered platform. Called SolarVille, the idea came about because Space10 decided to do research into how solar energy might change people’s lives in the future. But it’s hard not to see the lab’s research in the context of Ikea’s larger sustainability goals and initiatives. For instance, one segment of Ikea’s business, a franchise called Ingka that runs Ikea stores in 30 countries, has pledged to bring affordable solar technology to homes in all of these markets by 2025. Ikea has also been selling solar panels in the U.K. since 2013 and launched a battery and solar panel kit in 2017, also in the U.K.

Right now, SolarVille is a 1:50 scale model village, where the homes are decked out with mini solar panels that harvest energy from the sun. All the buildings are hardwired together, creating a microgrid that enables everyone to share their energy. In the concept, some people will generate excess energy either by using less energy themselves or by installing more solar panels. A blockchain technology platform will enable them to sell that extra energy to their neighbors without any intermediary–instead, the transactions between neighbors are logged in a secure and transparent ledger. Space10 says that the design is meant to be easy to use and install, and all the software that runs the blockchain is free.

Part of the project is meant to lower the cost of energy, since the blockchain platform wouldn’t require a company in the middle. “Centralized energy systems are often too slow and economically inadequate to reach the billion people who remain locked in energy poverty,” Bas Van De Poel, creative director at Space10, tells Fast Company in an email, referring to the higher costs of traditional electricity and the infrastructure that would be required to bring it to under-powered areas. “SolarVille showcases that, when working in tandem, technologies such as solar panels, microgrids, and blockchain open new opportunities: off-grid systems allowing people to leapfrog traditional grid electricity.”

KACO new energy is now launching its first hybrid inverter onto the market and is offering it together with the battery and mains disconnector as a system from a single source.

KACO new energy presents its hybrid inverter for the first time at the Energy Storage Europe show in Düsseldorf. With the acquisition of the storage provider Energy Depot last autumn, the German PV pioneer secured the market-ready technology. The inverter is now available as blueplanet hybrid 10.0 TL3. It is aimed at operators of residential and small commercial solar PV systems that want to combine the advantages of solar energy with power storage.

The blueplanet hybrid 10.0 TL3 is the control center of the solar-powered energy storage system: It provides connections for battery, PV system and public power grid. Several batteries can be connected to the hybrid inverter — even as a retrofit. In this way, it can always be adapted to the energy demand. The new hybrid inverter provides three-phase grid feeding and compensates for fluctuations in consumption within 100 milliseconds. When it feeds electricity into the grid, it achieves an efficiency of 98%, and a high 97% when charging and discharging the batteries. In addition, the inverter has excellent partial load characteristics.

KACO new energy offers the blueplanet hybrid 10.0 TL3 together with battery and mains disconnector as a complete package under the name blueplanet hy-store. It is the only storage system on the market that can also set up a three-phase stand-alone grid with a full 10 kilowatts of power. The next development stage envisages automatic island switching to enable reliable emergency power operation. This functionality is to be implemented by a software update.

In many electric utility markets, policymakers are exploring the next generation of renewable energy policies that will deliver the most value given the new reality of low-cost solar PV, wind and energy storage. Policies that encourage energy storage to be paired with solar or wind generation can have an outsized impact because these grid assets can together deliver firm capacity into peak periods when customer costs are the highest. If implemented effectively, the results are lower costs for ratepayers, increased resiliency and reduced emissions.

A Clean Peak Standard (CPS) is a relatively new policy tool that can increase the share of renewable energy resources used to meet peak demand. Now is the ideal time to implement Clean Peak Standards in the U.S. because there is a significant amount of peaking capacity that is over 40 years old, as shown in Figure 1. Over the next 20 years, about 152 GW of peaking capacity is expected to retire. For example, in North and South Carolina, 1.61 GW of winter peaking capacity is scheduled to retire by 2028 according to Duke Energy Carolinas and Duke Energy Progress.

Arizona and California have proposed a CPS, and in 2018 Massachusetts became the first state to establish a CPS requiring the delivery of a minimum percentage of kilowatt-hour sales from clean peak resources during system peak demand periods. Building upon these efforts, Energy Intelligence Partners (EIP) has developed a new CPS concept that improves the traditional CPS. It leverages the improving economics of energy storage (ES) to address the limitations of renewables and will help create a truly reliable clean grid.

ES has the capability to address the main drawback of renewable energy — its intermittency — and turn renewable energy resources into truly dispatchable assets. EIP developed an ES-centric CPS for North Carolina’s regulated monopoly electricity market, but it can be a model for other states with similar energy markets.

The energy storage-centric CPS (CPS-ES) requires that renewable energy generation is paired with ES. A portion of power delivered during designated peak periods must be generated by renewable energy and delivered by some combination of the renewable energy generator and paired ES. This means that unlike other CPS programs, generators are not just incentivized to deliver during peak periods, they are required.

March 6 (Renewables Now) – NEC Energy Solutions, a wholly-owned subsidiary of Japan’s NEC Corp (TYO:6701), announced today that it has commissioned a 2-MW/2-MWh lithium ion battery energy storage system in Chile.

Located in Arica, northern Chile, the system will serve Engie Energia Chile, the local business unit of French utility Engie SA (EPA:ENGI). Connected to an existing substation, the energy storage unit will provide spinning reserve and other ancillary services to help with the integration of solar photovoltaic (PV) and wind projects, the company said.

The installation uses a GSS grid storage solution and includes containerised lithium ion batteries, a power conversion system and NEC Energy Solutions’ AEROS controls system. The firm is also in charge of service and maintenance.

This is the first plant of its kind operated by Engie in the region, but is the third for NEC Energy Solutions in the country. In all, the latter has 34 MW of grid energy storage in Chile.

Last week’s Energy Storage Summit 2019 saw the great and the good of Europe’s energy storage sector gather at London’s Victoria Plaza for two days of discussion, debate and networking.

The Energy Storage News, Solar Power Portal and Current± editorial teams were present throughout the event, highlighting give key themes that emerged at a crucial time for the storage sector.

Deepening discussions and openness of plans and strategies
One big sign of maturity was the elevated level of discussions, now that the show has reached its fourth year. Topics previously off-limits due to commercial sensitivity or just a lack of experience from the field, were explored in depth.

Developers Zenobe Energy and Anesco, aggregator Kiwi Power and technology provider Belectric discussed the “Revised front-of-meter business model” with openness. For instance, Kiwi Power business development head Quentin Scrimshire said that the wholesale market might not offer as much opportunity in the UK as in other markets.

Anesco’s commercial operations director Lily Cole even gave a rough breakdown of the elements that comprise project costs: revenue streams, Capex, Opex and the cost of capital.

“An O&M for a battery is about £4,500 per megawatt. Then on top of that you have business rates, which is £5,500 per megawatt – but then you get a 0.48 factor against that, so it’s about £2,300 per megawatt. Then you’ve got insurance on that; whether you want to insure against revenue streams, in our case, about £700 to £1,000. Then you’ve got rent,” Cole said, explaining that that currently stands at about £1,000 per megawatt.

The record year for storage in 2018 reflects the increasing competitiveness of batteries and enhanced utility familiarity with the new technology.

Growth in FTM storage was especially pronounced in the fourth quarter, when the U.S. deployed 352 MWh of batteries. Many of those installations were used for capacity, the authors wrote, and had durations of more than four hours.

As in recent years, California led the nation for storage deployments as its utilities aim to meet the state’s ambitious energy storage mandates. Texas, New York and Hawaii also were hotspots for growth, the authors said.

Battery storage growth came despite more modest price reductions in lithium-ion technologies than researchers originally anticipated. While they had originally forecasted a 14% decline in battery prices, supply shortages meant overall price declines were only estimated at about 6%.

“2018 was also marked by battery supply shortages, as manufacturers committed capacity to the South Korean market to take advantage of incentives,” the authors wrote in a release. “Consequently, U.S. storage system price declines slowed in 2018, with some products even seeing slight price increases.”

Analysts expect those supply shortages to abate after the first half of this year as manufacturers bring new battery factories online. That will help drive growth in U.S. battery storage that could reach more than 4 GW of annual additions by the next decade.