With rapidly changing technology, I suspect that a book that is current will be hard to come by. As a newbie in the area, this is where I'd recommend researching to start
- your local building code requirements (this often dictates a system design more than anything) for such a photovoltaic (PV) solar system
- figure out what service you have (3-phase vs split phase or ?) Amp service level provided by utility and main load center (breaker panel) type and capacity. Any sub-panels, etc, Why? if an older house, with say only a 100A service from utility company, and a 100/125A busbar on main load center, you might be limited in how much PV you can add.. maybe... depending... ;^)
- understand the design implications of roof mount vs ground mount arrays (general rule of thumb is to use ground mount when practical possible) due to future roof maintenance implications, panel access, etc
- what are you trying to accomplish with solar electricity generation (partial vs full kW usage offset, future electrical consumption expectations (ie appliance electrification, EV, etc). See below on monitoring... first there is what you are trying to accomplish, then reality of lower PV production in winter, your specific site PV considerations (tree shading, mountains (number of direct sunlight on panels), etc), and then what makes sense financially (ie enabling to disconnect from local power grid entirely, and 100% self-generate tends to be expensive and not a good financial approach... but depends). vs simply optimizing utility bill (largely reducing, not entirely eliminating, grid power importing)
- understand the design implications of AC coupled (micro-inverter) vs DC optimized, vs DC string panel arrays . Personally, I'd say beware of anyone that one approach is always recommended (because.. not true.. it depends.. each has its own Pro's and Con's)
- local net metering rules (ie putting excess PV generated energy on local Power Company (PoCo) grid, and using that energy later. Early rules to incentivize PV installations provided very generous benefits (like using power grid as free battery), and such rules are going away.
- Based on net metering rules specific to your local power company, an energy storage system (ESS, ie whole house battery) may make financial sense (ie a positive return on investment [ROI]). Though you can decide on a battery for other reason than ROI.
- When dealing with a battery, you have to decide whether trying to
- only have enough kWh capacity to cover peak time-of-use rates (some places {like where I live} have MUCH higher electricity rates at certain time of the the day).. This is sometimes called demand-shifting (ie using PV (and grid?) to charge battery during times of excess solar and/or law rates, then using battery during peak charge rate times
- Whether you want backup power is grid is down (grid forming setup), vs a battery that only works when local utility power grid is working (grid following.. cheaper as a micro-grid interconnect device / MID is not required)
- ex - for those with a high variance (difference) from off-peak to peak time-of-use rates, a grid-following battery large enough to cover peak times may provide best ROI. However, you'll be annoyed when grid power goes down during daylight hours, and you can't use your PV/battery.. side note, many simpler AC or DC coupled PV systems are grid-following (ie grid power fails, and PV system stops working). a MID (grid-forming) device of some sort required to disconnect home from grid to allow PV and/or battery to keep working (for more on MIDs and recent technical developments, see this article https://iaeimagazine.org/evolving-t...-adaptors-and-microgrid-interconnect-devices/)
- Whether you want entire home backup vs only specific critical loads. This is often determined by cost and amount of energy required to cover entire home. For example, my peak kW usage is around 8kW (and that is with heat pump HVAC and PHEV charging (at 16A)... as such, many hybrid inverters can cover my entire house load, which is cheaper than getting either
- smart load solution (from upper-end SPAN type breaker panel setup or whatever similar solution exists in Europe) to various hybrid inverters that can have a few limited breakers smartly controlled, vs the old-school brute-force critical loads sub-panel [ie, battery only powers sub-panels (critical loads).. and that means moving circuits to new panel, and potentially re-wiring some circuits if certain outlets need to be broken into separate circuits (breakers)] There are those with primarily electrical appliances (where as I have many natural gas appliances like oven/stove, water heater, etc) that have MUCH higher peak kW usage... and that means either a more expensive inverter, or sometimes multiple inverters (can get expensive)...
- When planning, if you have natural gas or other non-grid powered appliances that might eventually want to cut over to PV/battery/grid-powered, then consider those loads in your peak capacity calculations
- Bottom line, with decreasing battery costs, whole house backup is sometimes cheaper than partial/critical loads only backup, if peak load is small enough and factoring in electrician labor... depends when going the do-it-yourself (DIY) route
- *IF* going backup route (ie a MID is present), then you need to consider system coordination for the following scenario... batteries are near full, and PV output exceeds house electrical load. In this case, the 'system' needs to signal PV system inverters to curtail production. The old-school brute-force approach is frequency shifting, but there can be more direct and granular communication .. but there are good standards for this, so check carefully. If using frequency shifting, be sure to understand implications and potential downsides.
- And you will probably want to look at a high level on virtual power plant options in your area (may or may not be something to consider)
- General rule of thumb is that energy efficiency on the load side is usually (at least for now) cheaper than adding PV/battery capacity (ie, beware trying to off-gird power old inefficient air conditioning systems.. or certain other systems)
- The other hot-button topic is local communication vs required 'cloud' (ie internet server) communication and control systems. Along the same lines, if you want reliable network communication, use Ethernet not WiFi (when connecting various components, when practical). Numerous vendors have gone out of business, stopping certain products from working (both solar and other)... so some folks (like myself) strongly prefer a system that does NOT require Internet communication to function. I'm ok with certain reporting, etc.. for me the question is on-going operations if company goes out of business, or extended internet communication outage. Local communication also comes into play if trying to do something like Home Assistant for various automation tasks. In North America, there is hope that bi-directional EV charging standards will drive cross-vendor communication standards related to smart home energy management... only time will tell if this happens. In the mean time, a single vendor solution can sometimes be the only route today to simple reliable sophisticated smart home energy management.
- when hooking up a hybrid-inverter, beware they often have longevity of typical north american natural gas hot-water heater. As such, best practice is to have a bypass switch installed enabling you to power house directly from grid if/when hybrid inverter fails, giving you time to troubleshoot and repair/replace (which could easily take longer, to much longer, than replacing a hot water heater as they aren't as common, not as readily available, not as standardized, etc). If you can trained and capable of working with live grid-powered service entrance cables, then this may be a low concern.. for most people, if hybrid inverter/MID fails while you are away from home, your significant other (partner/family) will likely want a simple "go flip this switch, and power will be restored
[from grid], and I'll deal with problem when I get home" type option. This also lets you do hybrid inverter maintenance (including outright replacement) while house still has power. If this appeals to you, be sure to plan wiring accordingly (due to extra costs involved, this is often not proposed/suggested)
Other things you may want to research
- residential EV charging using DC (not really a typical solution today, but coming? see Australia's Sigenergy’s Sigenstor 25kW Bi-Directional ESS/DC EV charger, Hybrid Inverter as an example of possible direction. For me, the single-phase output is too low to be practical, and some other missing features mean it isn't something I'd want... but I like the idea of limited DC EV charging to avoid the energy loss from excess AC/DC conversions (maybe). My hope.. .once local bi-directional EV charging and connection standards worked out locally, this type of solution will become more prevalent
- why some experts say trying to charge an EV from solar isn't practical (typically not cost-effective).. but how that might change with new bidirectional DC charging?? especially if not needing large amount of kWh daily for an EV
- If you are a research/data/knowledge geek, realize you are likely to get curious about your energy usage. A typical PV solution does simple energy monitoring of grid kW import/export and PV production (from which it is easy to calculate house consumption) [Typically these measurements are done using Consumption Tracking (CT) clamps]. But you are likely to want to know more about that home consumption. SPAN panels are the top-of-line type solution (offering both monitoring and individual circuit control), with something like the Emporia Vue 3 which does monitoring only (for a very small fraction of the price) .. depends on you budget
The above should be way more than enough to get started on understanding some system basics. After that, one can get into technical details of select system components, and by then you will have a high-level understanding of your system goals, constraints, etc. The art of possible is greatly expanded, but also includes options for those that are entirely off-grid (ie rural area where connecting to power grid is not feasible) that are WAY more expensive than a grid-tied solution
I hope this helps
