home energy storage systems

L Luke Product Manager, GreenMore · BIPV solar tiles, facades & storage Homeowners increasingly want clean energy without giving up how their house looks. Conventional panels do the job, but they are clearly an addition bolted on top of the roof. Solar roof tiles take a different route — the electricity generator becomes the roof covering itself. This article explains what they are, how they compare with panels, what they cost, and where a home battery does and does not help. What Are Solar Roof Tiles? Solar roof tiles — also called solar shingles — are photovoltaic units made to look and lay like a normal roof covering. Rather than fitting framed panels above an existing roof, the tiles replace the covering and follow its lines. At GreenMore we make two main families in our own factory: Curved three-arch tiles for traditional, clay-tile and premium profiles, such as our solar roof tiles. Flat photovoltaic tiles for cleaner, more modern planes. Each tile carries out three jobs at once: it finishes the roof, keeps the weather out and generates electricity. You can read more detail in our guide what is a triple-arch hantile. Why Homeowners Choose Them A roof that still looks like a roof The main reason is appearance. Tiles sit flush and follow the roof’s shape, so a heritage, traditional or carefully designed home keeps its character rather than carrying a visible rack of panels. Generation and weatherproofing in one layer Because the tiles replace the covering, you are not paying for a roof and then a second generation system on top of it. That single-layer logic is what makes the economics work, particularly on a new build or a roof that was going to be replaced anyway. Lower running costs The electricity generated is electricity you do not buy, and surplus can be exported under whatever scheme applies locally. The saving depends on your tariff, roof orientation and how much daytime generation you use in the house. Built for outdoor exposure Our tiles use laminated toughened glass and are rated for 5400 Pa static load, Class A fire performance and operation from −40 °C to +85 °C, so they handle wind, snow, hail and coastal humidity rather than being fragile indoor electronics. GreenMore Residential Wave-Shaped Building-Integrated Photovoltaic Roof Solar Tiles vs. Conventional Panels Both are mature, reliable technologies. The honest answer is that they suit different situations rather than one simply winning. Feature Solar roof tiles Conventional panels Appearance Flush, follows the roof; looks like tiling Framed modules on rails; clearly visible Power density Curved around 103 W/m²; flat near 200 W/m² Highest; least area per kW Cost Higher per kW, but includes the roof surface Lower for generation alone Best timing New builds and re-roofs Retrofits on a sound existing roof Role Roof covering and generator Generator only Do You Need a Home Battery? Solar tiles work fine on their own. During the day they power the house and export any surplus. A battery earns its place in two situations: when you are away during the day and most generation would otherwise be exported cheaply, and when you want backup during outages. It stores midday generation for the evening and, on an island-capable system, keeps key loads running if the grid fails. We explain the interaction in how solar roof tiles work with storage. A point worth making plainly: a grid-tied solar roof with a battery reduces your dependence on the grid, but it is not usually complete “energy independence.” Genuine off-grid living needs an oversized array, a larger battery bank and often a generator for long cloudy periods. You can compare options in our home battery range. What It Costs and How Long It Lasts Solar tiles cost more per kilowatt than conventional panels, but the fair comparison is against the combined cost of a new roof plus panels. On a building that needs re-roofing, the gap narrows considerably; on a sound existing roof where you only want generation, retrofit panels are usually the cheaper route. Our solar roof solutions are quoted per project against the roof area and the country. On warranties, the photovoltaic tiles carry a 25-year power output warranty, while the inverter, battery and other non-tile parts carry a 3-year warranty. These are separate figures and we never blur them into one number. Frequently Asked Questions Do solar roof tiles work on any roof? They work best on pitched roofs with good orientation and enough usable area. Because curved tiles produce less per square metre than large panels, a small or heavily shaded roof may not fit the capacity you want; we check this from your dimensions before recommending them. Can solar tiles be fitted to an existing roof? They are designed to replace the covering rather than sit over it, so retrofitting usually means re-roofing the relevant area. If your roof is still in good condition and you only want generation, conventional panels are generally the more economical choice. How much can a solar tile roof reduce bills? It depends on roof size, orientation, local sunlight and your daytime use, so there is no universal percentage. A realistic estimate is modelled from your actual bills and roof rather than promised up front. Do you supply the tiles and battery together? Yes. As the tile manufacturer we supply the roof and configure a compatible inverter and battery for your grid, so everything is matched and supported through one contact. See what fits your roof Send us your roof area and pitch, orientation, country and target capacity, and whether you want a battery. We will recommend tiles or panels based on the actual numbers. Use the contact page or email export@gmsolarkit.com. L Written by Luke — Product Manager, GreenMore Luke manages GreenMore's BIPV tile and home storage product line. He has worked on photovoltaic systems since 2017 and helps homeowners choose honestly between solar tiles, conventional panels and battery storage based on the roof and the real costs.

P Peter Lu Energy Storage Product Manager, GreenMore There is no single correct battery size for every home. A system that is too small runs out during the evening or a long outage; one that is too large costs more than it will ever save. The right number comes from three things: how much electricity the loads you care about actually use, how long you want them to run without the grid, and how much of that energy the battery can realistically deliver. This guide walks through all three and ends with a simple worked example. Step 1: Build your load profile Start from your electricity bill, which states daily or monthly kilowatt-hours, rather than guessing from a list of appliances. Then separate the loads you want to keep running during an outage or overnight from the ones you can do without. Refrigeration, lighting, internet, a fan or a small heat-pump circuit usually make the essential list; an electric oven, clothes dryer or whole-house air conditioning often do not. To make this concrete, read the nameplate power of each essential appliance and multiply by the hours it runs per day. A 150 W refrigerator cycling for 8 hours, for example, uses about 1.2 kWh. Add the essential loads together to get your daily critical load. A small efficient home might land near 5 kWh, a typical family home around 10 to 15 kWh, and a large home with electric heating considerably more. If your main goal is savings rather than backup, also check your utility's time-of-use schedule. Under a plan with a clear peak and off-peak gap, the battery should be large enough to shift a meaningful share of your evening consumption; where rates are flat all day, size mainly for backup and solar self-consumption. Treat any quoted prices as illustrative — tariffs differ by utility and change over time, so use your own plan. Step 2: Decide your backup target Next, decide how long the essential loads must run on their own. Most homes aim to cover one evening and night until solar returns, which is effectively a one-day target. Off-grid and weak-grid homes may want two days or more to ride through cloudy weather. Backup days multiply the energy you need, so this single decision has the biggest effect on cost. Basic backup — lights, refrigerator and communications for a short outage; roughly 3 to 5 kWh of usable energy. Comfort backup — adds heating or cooling, a water heater and kitchen circuits; commonly 8 to 15 kWh. Whole-house or off-grid — running the full home for a day or more; usually 20 kWh upward and often a generator for long stretches. Step 3: Apply depth of discharge and efficiency You cannot use 100% of a battery's nameplate capacity repeatedly without shortening its life. The usable share is set by the recommended depth of discharge (DoD), and some energy is lost in the inverter, cabling and battery itself. Lithium iron phosphate (LiFePO4) systems commonly allow about 90% DoD and run at a round-trip efficiency near 90%, but the exact figures come from the product datasheet, and it is sensible to leave a small margin rather than cycle at the limit every day. Battery capacity (kWh) = daily critical load × backup days ÷ (DoD × system efficiency) Worked example Suppose the essential loads total 12 kWh per day. For one night of backup with a DoD of 0.9 and efficiency of 0.9: 12 × 1 ÷ (0.9 × 0.9) ≈ 14.8 kWh Rounding up leaves headroom, so a system around 15 to 20 kWh fits a one-night target. If the same home wanted two days of autonomy, the requirement doubles to about 30 kWh — a decision worth comparing against adding a backup generator, which is cheaper for rare multi-day events. Note the distinction between nominal and usable capacity: a battery sold as a certain kWh delivers less to the wall, so always size from usable energy. Home situation Typical usable capacity Configuration Apartment or small house, short outages 5 to 10 kWh Single wall-mounted battery, single phase Family home, one-night backup 10 to 20 kWh Wall or stacked system, hybrid inverter Large home or villa, three-phase loads 20 to 30 kWh Stacked modules, three-phase inverter Off-grid or two-day autonomy 30 kWh+ Multiple modules, often with a generator Leave room to grow A modular battery lets you add capacity later, but only if the inverter and communication bus support it. It is common to start with enough storage for the essentials, add modules when an electric vehicle or heat pump arrives, and integrate solar on the same system. Confirm the expansion limit and that new modules are compatible before buying; not every wall-mounted battery can be extended, and mixing different generations can be restricted. GreenMore energy storage batteries support parallel expansion of up to 15 units What to check before you buy Match the battery and inverter. Their voltage windows, power rating and control protocol must be compatible. A battery is only as useful as the inverter it pairs with, so confirm the combination works rather than buying them separately on price. Check real certifications. Ask for the documents relevant to your market, such as CE and IEC for many regions, plus UN38.3 and MSDS for transport and handling. Safety testing such as IEC 62619 is a good sign; verify the certificate rather than relying on a logo. Compare usable capacity and warranty, not sticker size. Two batteries with the same nominal kWh can differ in usable energy, cycle life and warranty terms. Read the cycle definition and warranty period — GreenMore covers non-tile storage components for 3 years. Avoid undersizing on price. A battery that is regularly flattened or pushed past its limits will not reach its rated life. If budget is tight, protect the essential loads and expand later rather than running a small unit at its limit. You can see the residential range on our home energy storage category page and the home energy storage system product page. If you send us your bill, appliance list, country and backup target, we can work through the sizing with you — use the contact page or email export@gmsolarkit.com. FAQ Is a 5 kWh battery enough for a house? For a small efficient home that only needs to keep lights, a refrigerator and internet through a short outage, around 5 kWh of usable storage can be enough. It will not run heating, cooling or the whole home overnight, and it is tight where outages last more than a few hours. What is the most common home battery size? Most grid-connected family homes land between 10 and 20 kWh of usable capacity, which covers the essential loads through one night. The right point within that range depends on your evening consumption, whether you heat with electricity and how long local outages tend to last. Should I use nominal or usable capacity when sizing? Use usable capacity. Nominal capacity is the battery's full rating; usable capacity is what remains after the DoD and efficiency limits. A 12 kWh nominal battery might deliver around 10 kWh to your appliances, so sizing from usable energy avoids coming up short. Is it cheaper to add a battery or a generator for long outages? For frequent short outages and daily savings, a battery is clean, quiet and automatic. For rare multi-day events, a generator — or a hybrid system that uses a battery first and a generator for extended bad weather — usually costs less than buying enough storage for several days of autonomy. P Written by Peter Lu — Energy Storage Product Manager, GreenMore Peter works with distributors, installers and system integrators to size residential and commercial storage around real load profiles. He focuses on LiFePO4 systems that match the inverter, grid rules and backup needs of each destination market.