11th Energy Storage World Forum (16+17 May) – LARGE SCALE APPLICATIONS FOCUS
RESIDENTIAL ENERGY STORAGE FORUM: 2 Days ONLY (14+15 May)
11th Energy Storage World Forum – LARGE SCALE APPLICATIONS FOCUS (16+17+18 May)
Choose from Masterclass A or B (15th May 2018) Tuesday 15th MAY – Ticket price 790 Euros or 500 Euros as a Package
While the benefits of solar-plus-storage – increased energy independence, reduced energy bills and lower emissions – are well-known, prices are finally reaching a point where systems are accessible for residential and commercial users.
Whether installing a complete solar battery storage system or adding energy storage to an existing photovoltaic array, one of the first questions to come up is “How much capacity is required?”. We will take a look at the factors are taken into account when assessing what size solar array or battery capacity is best for an application.
This guide is intended as a starting point – individual factors such as equipment and installation costs, electricity rates and grid stability will vary depending between countries and depending on the year.
The ideal size of solar and storage will depend upon the purpose of the installation. The two most cited reasons behind adding solar battery storage capacity are:
While often these two factors go hand-in-hand, aiming for complete self-sufficiency from the grid requires a much higher investment in energy storage than merely reduce peak time use. This is related to the following section:
To be completely “off-grid” and energy independent, both solar power generation and energy storage must be over-sized in case of a power outages. The upfront costs involved are expensive – but for most clients, this level of energy self-sufficiency is far beyond their requirements.
Decreasing the level of energy independence decreases the upfront installation costs. From highest to lowest:
For example, for a business in a remote area with an unstable local power grid, complete or high self-sufficiency could be worth the investment, especially if the costs associated with an outage are high. On the other hand, an industrial property whose electricity costs are mainly related to time-of-use would see the fastest return by investing in enough energy storage to achieve peak time self-sufficiency.
There are several factors to consider relating to local electricity rates.
A rule of thumb for solar arrays without battery storage is to aim to consume 30% of the total solar power generated. The capacity that this translates to will vary wildly depending on location-based factors – what direction the PV panels are facing, local cloud coverage, daily hours of sunshine. To store energy, the solar capacity must be increased past this level.
The energy storage component is more complicated. There is no point in having more battery capacity than there is energy to store. The larger the available solar panel array and the greater the difference between peak and off-peak rates (allowing the cheaper rates to top up the battery levels), the better the economics of larger battery systems.
The electricity usage pattern will affect the optimum relative proportions of the solar-plus-storage system. There are five typical usage patterns:
A building with pattern 4, Day Focus, can adequately supply its energy needs from just self-generated solar power without the need for much additional storage, if any. The more energy is consumed outside of daylight hours, the more the building or development will rely upon stored energy.
If you want to know more about this and other topics directly from end users of energy storage technologies join us at one of these energy storage conference: The Energy Storage World Forum (Grid Scale Applications), or The Residential Energy Storage Forum, or one of our Training Courses.
Storing heat for later use is not a new prospect, and has not created the same buzz as exciting new battery chemistries. Nevertheless, it offers many advantages to reduce pressure on power grids. For now, its usage for grid-scale applications has not yet taken off – but advances in the field could make this a thing of the past.
While thermal energy storage offers great advantages to make use of surplus heat and lower pressure on the grid, in its current form, it has limited suitability for grid-scale applications. However, this lowered electricity demand does increase grid stability overall. Additionally, the success of molten salt thermal storage, as well as research into the field of latent heat thermal storage are likely to make grid applications more viable in the future.